I believe is D because the other ones are just weird
the answer is A to this. I might have it confused with a different book.
I’m so sorry if i’m wrong but for the first question i believe the answer is 2 and for the second question i believe it’s 1
1d) was designed (long time ago so past tense)
2d) Has been repaired (It is still going on the present, this year)
3c) Had discovered (He discovered America long time ago)
4a) To have worked (worked long ago when he was young)
Hope it helps!