Which sentence most clearly uses concrete description to make the reader feel excitement? a. the apes lounged and scratched in the hay after their midday meal, their eyes strikingly human. b. the zookeeper walked back and forth on the walkway, tossing vegetables down to the gorillas. c. slap. without warning, the gorilla hit the glass of his enclosure. tourists dropped their cameras. d. at woodlawn zoo, we try to recreate each animal's natural habitat. come for a fun experience!

The right answer is the C) "Slap. Without warning, the gorilla hit the glass of his enclosure. Tourists dropped their cameras."

Explanation: Just to elaborate a little on the answer, it can be added that options B and D can be easily discarded, since option B is describing a customary action performed by the zookeeper, and, in spite of the exclamation mark, option D is not the one that entices the reader the most. By using short and descriptive sentences, starting with the word "slap" followed by a period, and describing a thrilling action, the sentence in option C is the one that clearly uses concrete description to most effectively persuade the reader and catch his or her attention. It is possible to visualize the gorilla's unexpected action and the tourists' reaction.    

Slap. Without warning, the gorilla hit the glass of his enclosure. Tourists dropped their cameras."

Explanation:

to not go near anything hot