Hello
Can’t we use a word like ingenuity in the blank? Because when I see the word “but” I feel like there will be a contrast with his naive or gullible impression. Like, he looks young and naive but he is a clever dude.
There’s already contrast in this sentence between “realized” and “surprised”.
So the logic is that they knew something, but were still surprised about the same thing.
“clever” would not work here. If we realized john was naive, it wouldn’t be unexpected to be “surprised at his celeverness”
Oh I see, it makes sense now. Thank you.