1．_____for the traffic jam,I should have covered fifty miles

1．_____for the traffic jam,I should have covered fifty miles.
A.Had it not been
B.Had it been
C.It has not been
D.Has it not been
2．______mainly for the invention of the telephone,Alexander Graham Bell devoted his life to helping the deaf.
A.He is remembered
B.To remember
C.While remembering
D.Though remembered
3．in no way____from practice
A.teaching in school can be separated
B.teaching can be separated in school
C.can teaching in school be separated
D.can separated teaching be in school
4．It was in 1949____New China was founded.
A.when
B.that
C.in which
D.which