Answer:
D. He will keep an eye on Angie and Gordon
Explanation:
The sentence explained that despite Angie's excitement about the fall banquet and Gordon and his mom coming to pick them, her father would be present at the party as if he were a member of the United States Secret Service.
This security agency are known for monitoring an environment to ensure the safety of the people in it. Therefore, the statement about Angie's father means that he will keep an eye on Angie and Gordon at the party.