When he first started in university, he really felt at（ ）with ec

When he first started in university, he really felt at（ ）with economics.
A、shore
B、sea
C、ocean
D、bank
【正确答案】：B
【题目解析】：feel at sea：茫然不知所措。选B。句意：刚开始进大学学习时，他对经济学真的感到不知所措。