Really interesting one! One thing, when you get to 2 objects, it is really easy to spot the answer after seeing just one object different - maybe some objects can repeat in the answers so if I see one, I still need to inspect the other.
Also, control related, I agree with movement as being weird when locked. Clicking outside the choices and moving doesn't click. Maybe the movement can be let free and the players can have a Hold to pick answer system - like Hold TAB, mouse locks, pick answer, or something similar.
Really short otherwise, I was really looking forward for a couple more levels as I really loved the art style and atmosphere, combined with the voice lines, I was ready to be sucked in.