You are called for a man who is not acting right. His wife says he was outside working in the garden

You are called for a man who is not acting right. His wife says he was outside working in the garden but didn't come in for lunch when he was called. She went to check on him and found him sitting next to a stump, confused. You assessment shows a pulse rate of 58, blood pressure of 186/82, respirations of 16, and one of his pupils is dilated. You are unable to detect any signs of trauma and you don't see any obvious indication that he has fallen. You should suspect a(n):
A) insecticide poisoning.
B) open head injury.
C) nontraumatic brain injury.
D) closed head injury.