宾语从句 求1.I didn't know __ they could pass the exam or not.A w

宾语从句 求
1.I didn't know __ they could pass the exam or not.
A why B when C that D whether
2.I watched that girl for a long time and wanted to know __.
A whether I have seen her before B where I had seen her befor
C that I had seen her before D when did I see her
3.If you __ him tomorrow,please ask him if he __ to work on the farm with us.
A see,goes B will see,goes C will se,will go D see,will go