各位英语高手请帮我解决几道英语状语从句选择题。谢谢

Question

1.the cost of living in Glasgow is among the lowest in Britain,_________the quality of life is probably one of the highest.
A.since B.when C.as D.while
2.A man cannot smile like a child _____a child smiles whith eyes, while a man smiles with his lips alone.
A.so B.but C.and D.for
3.In place, too,the Red Cross is expected to send help _____there is human suffering.
A.whoever B.however C.whatever D.wherever
4.________ environmental damage is done , it takes many years for the ecosystem to recover.
A.even if B.if only C.while D.once
5.the old tower must be saved,______the cost.
A.however B.whatever C.whichever D.wherever
6.we thought there were 35 students in the dining hall,_____,in fact,there were 40
A.while B.whether C.what D.which

Answer 1

1 D
2 D
3 D
4 D
5 B
6 A