Hello,

Yes, it is mandatory for a candidate to attempt all questions of KVPY SA stream including Biology. Stream Sa of KVPY 2018 will consist of 60 and 20 questions in Part I and part II respectively from Physics, Chemistry, Mathematics and Biology. The level of Biology will be of class 10th. Thus, if the candidate thoroughly goes through the Biology textbook of NCERT and practices the previous years' question papers of KVPY, he/she should be easily able to clear the subject. Although one must be careful while answering as every incorrect attempt will attract a penalty of 0.25 marks.

All the best!

 KVPY syllabus includes major subjects and topics covered in  SA, SX and SB. All the streams comprise 20 questions from Maths, Science, Physics and Biology. In SA, Part 1 includes 15 questions and part 2 consists of 5 questions. You can also check the further information regarding the syllabus with the given below link.

https://school.careers360.com/articles/kvpy-syllabus

Good Luck!