Select from the following.
1). trees
2). it needs them
3). knives
4). Males and females
5). adding heat
6). guns
7). Sensing light
8). lowered energy cost
Q: You are presented with the quiz "How do wolves hunt?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "eyes are used for seeing by animals by sensing light" and "wolves use their teeth, feet, eyes, nose, and ears to hunt". So, what's the best answer to the question?
A:
7).