I'm satisfied to vote "B." I wouldn't have had anything to do with a show I came to identify as a "C" because I don't see any reason to make an average show appointment television.
If it were just 'one' show, then yeah, I see your point. But some elements of TREK just didn't go over...in fact, here are generally accepted views
(though I do not agree with all of them)
TOS season 3 was not that good
TMP didn't live up to hype
TREK movies GENERATION/INSURECTION/ NEMESIS/FRONTIER were not that good
TNG season 1, and part of season 2, were not that good
DS9..seasons 1 and 2 were so so, 3 okay, 4-7 great
Voy..some of it good, some of it bad
Enterprise...season 1 and 2 were not good..3 so/so..4 not bad
That's alot of 'iffy' grades there if you agree with any of it...so I think a C isn't bad...actually, a C average show that has over 700 hours to it can't be that bad.
Rob