C is most likely the correct answer.
A sentence that makes statements has a pattern that starts with a subject and followed by a verb.
Subject + Verb
Subject + Verb + Complement
Subject + Verb + Direct Object
Subject + Verb + Indirect Object + Direct Object
Subject + Verb + Direct Object + Complement
An interrogative sentence or a sentence that asks question begins with an interrogative word followed by a verb then the subject.
Interrogative words are What, when, where, why, how, which, who, and whom.
Interrogative Word + Verb + Subject
Interrogative word + Verb + Subject + Verb
I would say the best answer is A, he hides behind a tree. I was in between A and D, but one can run in a park.
B wouldn't work because him being dressed in ordinary street clothes doesn't show that he's afraid of something.
C wouldn't work because although yes, he was panting, that could mean that he's just tired; not necessarily, scared.
The man hiding behind the tree is the best evidence for the conclusion of him being afraid of something. Also in the passage it states, "....he moved behind a tree. Seeming not to notice my presence, he stood with his back against the trunk, panting."
