Question

Which answer is the sentence fragment? A. A game-tying double in the top of the seventh inning. B. My softball league is very competitive. C. We were able to win in extra innings thanks to some timely hitting. D. Our pitcher looked exhausted after playing in back-to-back games.

Answer 1

The answer is A because that sentence doesn't have a verb
Complete Sentences = Subject + Verb + Adjective (optional)
Ex: She               is                    swimming.
         ↓                  ↓                          ↓
      subject    to be verb            verb

Answer 2

For your question the answer is A.
  
                                      Hope this helps:)