Below 150, and I don't even need to take the quiz. I know Iowa's entire delegation (Hinson, Miller-Meeks, Axne, Feenstra, in that order) as well as some notable ones (Pelosi, Schiff, Ocasio-Cortez, Greene, McCarthy, Cheney, etc.) and other various members (Rochester, Young, Duncan, etc.), although 435 is a big number. Probably low-to-semi-mid double digits.
If I were to take the quiz I'd probably just do 40 minutes of a bunch of blind guesses using common surnames like 'Johnson' and 'Smith' and whatnot.