（）总吨以上的油轮和（）总吨以上的非油轮及拖带（）总吨以上油驳的拖轮应按规定编制油污应急计划。

— Could you tell me           last night?

— He went home by taxi.

A．what Tom did

B．what Tom was doing

C．how Tom goes home

D．how Tom went home