Ididnt do the lesson which sentence is punctuated correctly?

a. jennifer suggested, "let's take a break."
b. gary gasped "i think that's a skunk."
c. "look, over there" exclaimed phillip!
d. "do we know how far this trail goes"? said amy, reviewing the map.

A. Jennifer suggested, "Let's take a break." 
It has all the necessary components in the sentence. There is a comma before the quotation and a punctuation mark at the end of the quotation. The rest of the sentences are either missing punctuation, have a capitalized letter when there shouldn't be, and misplaced punctuation marks.

Hope this helps :)