I think the correct answer is C. his obvious aggressiveness.
It says in the passage, "A few minutes later he bolts suddenly into the woods, achieving full speed, almost forty miles per hour, for forty or fifty yards before he begins to skid, to lunge at a lodgepole pine cone."
The way the wolf acted towards the cone, and the way he bolted at almost forty miles per hour, shows his alertness, and how he is aggressive to anyone who tries to fight him, or just in general his aggressiveness.
Hope this helps, have a good day. c;
