Could you help me with some test questions?

Friend of mine asked me to help him out on some test questions. According to the test, only one answer per question is correct. I wasn't sure about these:

He writes each appointment in his diary ...... forget it.
a) because
b) for not to
c) so as not to
d) in order to

Note: They all sound nonsensical to me. Unless, c) is acceptable, but so old fashioned that I haven't heard it yet.

She said she ...... anything like that before.
a) wasn't seen
b) hadn't seen
c) hasn't seen
d) wouldn't see

Note: I recommended b).

...... many times I tell him, he always forgets to pass on phone messages.
a) Whenever
b) Wherever
c) Whatever
d) However

Note: all options sound weird to me, but perhaps in old, posh English you would have said "however many times."

..... he was nearly 75, he could still beat me at tennis.
a) Since
b) Despite
c) In spite of
d) Although

Note: I presume d) is right. However, I do not see a problem with b) either.

I was getting out of my car when I saw her ..... by.
a) to pass
b) pass
c) passed
d) passes

Note: I would prefer "passing," but from given options I would probably choose b).

..... traffic in the city center at rush hour.
a) It is always heavy
b) There's always many
c) It is always much
d) There's always heavy

Note: Obviously d) is correct, but I do not see a problem with a) if the traffic is the object. I know that "there's" serves as auxiliary, but you could say it pertains to the location of city center, while "it is" focuses more on the traffic.