Even though the OA is different I would argue for D) unless someone can provide convincing reasoning

It says fewer than 1/2 had strawberry. I would say let 9 be that number since we are trying to maxmize girls and particularly girls who eat choclate icecream. If [spoiler]OA (A)[/spoiler] tells us this then why not statement II??[/spoiler]

A

stmnt 1: we have information for 9+8=17 people, 30 attended, so 30-17=13 people can be boys/girls and can have choco/strawberry. if we want the max number of girls who had choco, its possible only if all 13 people were girls and had chocolate. sufficient

stmnt 2: less than 1/2 ate strawberry. no information on total number of attendees.
say 9 had strawberry, so total number of attendees>18
if attendees=19, max girls for chocolate: 2
if attendees=20, max girls for chocolate: 3
we dont have a definite maximum number of girls for chocolate. insufficient

Regarding Choice (B):

You can cap the number of girls who have Strawberry ice cream at 9.
But what about the boys who had strawberry ice cream? This number is unbounded.
Because the number of kids who had strawberry ice cream is less than half of the total number of kids, this causes the number of children who had chcoloate ice cream to be unbounded. Therfore, the maximum number of girls who had chcoloate ice cream is unbounded.

cramya wrote:Even though the OA is different I would argue for D) unless someone can provide convincing reasoning

It says fewer than 1/2 had strawberry. I would say let 9 be that number since we are trying to maxmize girls and particularly girls who eat choclate icecream. If [spoiler]OA (A)[/spoiler] tells us this then why not statement II??[/spoiler]