请教5道名词性从句的题目,希望大家多多指教,

请教5道名词性从句的题目,希望大家多多指教,
16.it wasn't clear at that time______we met again so soon.
a.why b.when c.that d.where 我选B,
17.doing everything well depends on______we have enough confidence.
a.what b.which c.if d.whether 我选B,
18.--are you firmlyagainst the independence move bytaiwan?
--of course.that is______our basic inferest lies.
a.why b.when c.where d.what我选D,
19.we haven't received the reply______we should start the movement.
a.which b.that c.whether d.why 我选B,
20.the bus passed through the street______people thought was too high a speed.
a.at which b.what c.at what d.which 我选了A,
21.______you said yesterday is different______the fact.
a.that...with b.what...with c.what...from d.that...from 我选B,
22.Mary is surprised______you have told her and ______you have given to her.
a.everything that...all that b.at what...that what c.what...all what d.at what...all that 我选B,