Government & Defence Entrance Exam

Hi Hari,
Here are the ways in which you can join Naval Academy:
1. NDA/NA entry- only male candidates are allowed for NDA/NA. Age limit for candidates is 16-19 years. Education qualification required is 10+2 with physics and maths subjects. To join the national defence academy (NDA), aspirants need to appear in written exam and in the service selection board (SSB) interview process which is handled by UPSC.
2. B.Tech entry- only unmarried male candidates are eligible to make use of this entry mode who are between the age of 16 -19 years of age. 10+2 Science stream with physics and mathematics subjects, with minimum 70% marks in PCM subjects and minimum 50% marks is required in English subject (10th or 12th class). This is a new entry of navy. SSB calls are made directly to candidates having the 12th percentage above the cut off percentage.
3. CDSE-male graduates who have done B.Sc. With physics and mathematics or Bachelor of engineering can apply for naval academy.
4. Other graduate entries- graduates and final year students are eligible to apply for this entry. There is no written test, the calls are directly made for SSB based on cut-off percentage of the qualifying exam. Age limit between 18-25 years is allowed.

I found these are the main and most commonly offered B.Sc. Subjects. Biology
Biochemistry
Botany
Chemistry
Computer Science
Electronics
Environmental Science
Mathematics
Physics
Zoology
And now these are the optional subjects available in UPSC Mains exam. Agriculture
Management
Animal Husbandry and Veterinary Science
Mathematics
Anthropology
Mechanical Engineering
Botany
Medical Science
Chemistry
Philosophy
Civil Engineering
Physics
Commerce and Accountancy
Political Science and International Relations
Economics
Psychology
Electrical Engineering
Public Administration
Geography
Sociology
Geology
Statistics
History
Zoology
Law
Literature of any one of the following languages :
Assamese, Bengali, Bodo, Dogri, Gujarati, Hindi, Kannada, Kashmir, Konkani, Maithili, Malayalam, Manipur, Marathi, Nepali, Oriya, Punjabi, Sanskrit, Santhali, Sindhi, Tamil, Telugu, Urdu and, English. Highlighted subjects are mainly available in Mains exam according to your B.Sc. Study. Regards.