Chain rule on three functions

Solidify your understanding of the chain rule by practicing it on triple compositions.

Problem

If F, left parenthesis, x, right parenthesis, equals, sine, start superscript, 2, end superscript, left parenthesis, 3, x, right parenthesis, what is a rule for F, space, prime, left parenthesis, x, right parenthesis?
Please choose from one of the following options.
Get 3 answers correct in a row