A: at six in the morning (IV: at, in). B: rushed into my room gasping for breath (I: into, for). C: In his work... at missing part (II: In, at). D: to office on foot (III: to, on). Hence A-IV, B-I, C-II, D-III.
Note: The original sentences for C and D contain transcription gaps, so prepositions were matched by best fit to standard collocations.