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Hello Abha,
Ask your daughter to evaluate herself by solving one or two mock papers. By this, she will get to understand her weak areas.
There are a number of books available in the market for the preparation of the same.
For QA :
Arun Sharma: How to prepare for Quantitative Ability for CAT
How to Prepare for the CAT Common Admissions Test by Muhamed Muneer
Quantitative Aptitude for Competitive Examinations by Abhijit Guha
Quantitative Aptitude for CAT and Other MBA Entrance Exams by Trishna Knowledge Systems Pearson
Books for Verbal and Reading Comprehension:
How to Prepare for the Verbal Ability and Reading Comprehension for CAT by Arun Sharma and Meenakshi Upadhyay
Nishit Sinha's Verbal Ability and Logical Reasoning
Norman Lewis Word Power Made Easy
Books for Data Interpretation & Logical Reasoning :
How to Prepare for Data Interpretation & Logical Reasoning for CAT by Arun Sharma
Trishna's Verbal Ability And Logical Reasoning For CAT And Other MBA Examinations by TIME
Along with all these, ask your daughter to read English newspaper daily, accompany her with English novels, etc., this will build her vocab.
Practice is key to success.
Also, make sure she focusses on time management.
Good luck.

The difference as the name suggests is in the mode of study, both are designed for different sections of people and both are relevant looking at the cause for which MBA is being done.
Regular courses are classroom session courses where students have to attend classes, this is nothing but full-time MBA which requires your complete commitment for two years. This is the most preferred by recruiters and organisations.
Distance/ correspondence courses are more about self-study where the study material is sent to the student and they have to understand and learn it on their own. The main advantage of this is fees is low as compared to executive and full-time. In distance MBA, you'll have classes once or twice during the weekends, and you'll have exams twice a year.