Please explain the following 46th question with reason.

Dear Student,
46.
Assertion:

Hence, assertion is correct.

Reason:
Electron has less mass than the proton.
Hence, reason is also correct.
But both electron and proton have same radius of path because they have equal charge except their signs. 
i.e. q_e = q_p
So, their radius is same because of their charge not because the electron has less mass than proton. 

Therefore, option b is correct.

Regards