Choose the best preposition.

Here's the detailed solution for the preposition selection task: 1) in the morning -> in, 2) Sunday -> on, 3) Tuesday afternoon -> on, 4) spring -> in, 5) noon/midday -> at, 6) February -> in, 7) winter -> in, 8) 2013 -> in, 9) my birthday -> on, 10) a weekday -> on, 11) the evening -> in, 12) bedtime -> at, 13) a holiday -> on, 14) 10:30 -> at, 15) midnight -> at, 16) the weekend -> at, 17) Monday morning -> on, 18) May 5 -> on, 19) the afternoon -> in, 20) night -> at, 21) the 1980s -> in, 22) summer -> in, 23) Wednesday -> on, 24) fall/autumn -> in.