CDS

You can start with the NCERTs to build the foundation of concepts for the CDS exam. Here is the list of paper-wise suggested books by toppers to prepare for the CDS:
1. Elementary Mathematics: For this paper, you can refer to NCERT mathematics. Additionally, you can take help from RS Aggarwal's Mathematics for CDS or Quantitative Aptitude for Competitive Examinations. You can also refer to the Pathfinder for CDS book for this paper.
2. General Awareness: The syllabus of this paper is huge, so you must refer to the NCERTs for this section. In addition, you can refer to the Manohar Panday or Manorama Yearbook. You must regularly read the newspaper to stay updated with Current Affairs that will help you in SSB.
3. English Language: To prepare the grammar section of this paper, you can refer to the Wren and Martin book. For other topics, you can refer to Objective General English by SP Bakshi and Norman Lewis's vocabulary book.

The syllabus of the CDS exam can be divided into three major subjects: math, English and general knowledge. For those who prefer OTA in their application, there is no math paper. The following is the CDS entrance examination syllabus:
1. Elementary Mathematics: You have two hours to complete the 100 questions on this paper. Questions on number systems, arithmetic, Algebra variations, geometry, and other topics are included in the subject.
2. English Language: Questions on topics like comprehension, vocabulary, word substitution, spotting errors, sentence structure, word choice, etc. Are included in this paper.
3. General Knowledge: Questions based on GK topics and current events are asked in this paper. It asks questions about defense, awards, defense, history, economics, and more. The complete CDS exam syllabus is available at this Shiksha Page: https://www.shiksha.com/exams/cds-exam-syllabus.

The CDS preparation requires you to study with focus until the exam day. Here are some last-minute things you need to do before the CDS exam:
1. A month prior to the exam, stop reading all new material.
2. Examine papers from previous years to identify key themes that require multiple revisions.
3. To improve on test day, check your accuracy rate with a thorough practice test.
4. The important facts and formulas must be at your fingertips.
5. Begin preparing how you will approach the exam questions on the day of the written test.
6. Make sure you have all of the necessary items with you, such as your admit card.
7. Look after your health because you will have to take two or three papers on exam day.

The SSB stage of CDS is comparably more challenging than the written stage. It is tough due to the following reasons:
1. The SSB process lasts for six days, which makes it appear tough to crack.
2. With every test, candidates get rejected; this creates psychological pressure on aspirants.
3. More than knowledge, your suitability for defense is tested, which makes SSB unpredictable in nature.
4. You cannot prepare for the SSB with traditional books; instead, you need to appear in mock SSBs.
5. There are psychological and group tests, which make it difficult to be pre-prepared
However, with proper dedication and focused preparation, you can clear this stage.

The CDS exam is conducted for entry into OTA, IMA, AFA, and INA. This exam is divided into two types; the papers for IMA, AFA, and INA are the same, whereas for OTA there are no math papers. Depending on the academy you are aiming for, you can prepare with the help of expert tips.
1. Read about the exam syllabus and pattern to help you choose your study materials.
2. You need to focus on the concepts at the beginning in order to perform well on the elementary mathematics paper.
3. The NCERT books will be helpful from class IX onwards before moving on to math reference material.
4. You can use a grammar book by Wren and Martin or another author to study for the English section.
5. For the GK section, NCERT books are largely adequate.
6. If you are aiming for OTA, you can concentrate on the GK and English because the math paper is not required.
7. You must devote enough time to the math paper for other academies.
8. Practice as much as you can over the past two months because you will need to answer about 100 questions in two hours.
9. As you prepare, read newspapers and magazines to stay updated on current events.
10. Begin engaging in physical activity that will help you get ready for the SSB.

Both the Air Force Common Admission Test and the combined defense services are conducted to select suitable candidates for training in the academies for the post of commissioned officer in the Indian Armed Forces. While the complete AFCAT procedure is conducted by the Air Force and the CDS exam is conducted by UPSC The SSB for both exams is conducted by respective SSB boards. Selected students go through the SSB interview, and those who are recommended by the Services Selection Board undergo a medical examination. Only students declared medically fit are issued joining letters, subject to their rank in the final merit list calculated on the basis of the aggregate mark in written and SSB interviews.

B.A will be a better option if you want to make your career by clearing CDS exam. But for INA and Air force Academy you must have a degree in Engineering.
For INA: The aspirants must have a degree in Engineering. For Air Force Academy: The aspirants should have passed 12th standard with Physics and Mathematics and having a degree from a recognised university or Bachelors degree in engineering / technology. As we Know Why all prefer B.A. For CDS preparation because there are three different exams are organised by UPSC.
EXAM-I Elementary mathematics
EXAM-II English
EXAM-III General studies
So, if you go for B.A. for your graduation, you will have an advantage of preparing for third exam in parallel with your graduation. But you should choose subjects wisely as per exam syllabus because if your sociology and all this will not be beneficial as per your target. Believe me GK of CDS is quite tough. Questions are also asked about world. Most importantly, you have to gain at least 20% in each exam so that your OMR sheets go for checking. H

If you want to have a long-term career in the army, then IMA is a better choice, whereas if you just want to live in the army for a few years, then OTA is better.
1. The basic difference between IMA and OTA is that the Indian Military Academy is for permanent commissioned officers who will serve up to 30 years, whereas the Officer Training Academy, Chennai, is for short-service commissioned officers who can serve up to 14 years maximum in the army. Hence, you will have the option of leaving the army after your compulsory service of ten years as an SSC officer in OTA.
2. Also, those who don't like mathematics can skip the compulsory math paper and opt for OTA. To join IMA, you need to score higher in the CDS exam.
3. OTA also has cadets of both genders, whereas IMA only has male cadets. Both academies are reputed in the country and were established for different purposes. You can either opt for OTA or IMA if you have allocated both. Most of the male army aspirants usually go for IMA, whereas for girls, only the OTA option is there.

No, there is no strong data available that all short-service officers (OTA) do corporate jobs after serving for 10 years in the army. This is for multiple reasons:
1. Some officers prefer to extend their service tenure for four more years, as per army rules.
2. Around 5 percent get a permanent commission, depending on the vacancy.
3. Some other officers prefer to go for other government jobs, such as railways, as there are relaxations and quotas for ex-servicemen in many government jobs.
4. Some prefer to do higher studies, such as an MBA or Ph.D. before starting a new career.
5. Some other SSC officers choose to guide defense aspirants to achieve their goals. Therefore, not all SSC officers choose to take this path to start a new career after retirement.