Test-question

[Rustamsher]

Hello,Alan

I have a question and I'm at a loss which answer to choose:

The show ... longer so that we ... more time together.

(a) should have lasted/could spend
(b) had better last/were able to spend
(c) might be lasting/can spend
(d) used to last/ have been spending

At a first glance, I was prone to choosing (a), but it feels that (c) can also be correct.
Which answer is grammatically correct or are both correct?
Could you please give your explanation on both (a) and (c)?

Many thanks.

[Alan]

Yes, (c), although unidiomatic, would be grammatically possible & meaningful.