Green , and ... hot . The tropics , then , for all that she 'd been in an air conditioned bedroom on the Eastern Seaboard not 10 seconds before . She did n't make a sound , and then she heard it . A footstep , behind her .

Question: Why did she hear a footstep behind her ?
Answer: Because she was in an air conditioned bedroom .Because she was in the tropics .None of the above choices .Because she was green and hot .