I thought as well! The OA was wrong..
Thanks for the inputs!
I would go with C.
1. If univ has accepted an applicant this doesn't necessarily mean that this applicant will enroll - Insuff
2. You dont know how many are accepted - Insuff
Together you can canculate the %age as follows
Let x be total applicants who enquired
then 0.5x submit application
by 1 . 0.15(0.5X) are accepted
by 2 0.8(0.15(0.5x)) enroll ( assuming sending deposit means enrolling)
so if total 05.x people submit application .. 0.8*0.15*0.5X people enroll , therefore the percentage can be calculated