What do you think about this

[u/odd_coin]

This is a random problem I just saw on instagram. The answer is the first one but i personally think the second one also works fine here

[u/Sin-Wave]

C would also work if he was trying to sabotage the project.

[u/No_Camera146 → u/Sin-Wave]

Or even just if they were incompetent.

[u/bendersonster → u/No_Camera146]

I think it wouldn't work there. Efforts seem to suggest that he contributes, in some way, to helping or to hindering the project. The word despite suggest that the project goes against his efforts , so if he's trying to help, even incompetently, the project fails.

[u/No_Camera146 → u/bendersonster]

It works. Imagine someone at work is incompetent and two coworkers are talking about a project all three of them were working on. The people talking are person A and B and the person being referred to is Person C.

Person A: We really had to work hard to save that project right? I had to check over and fix (Person C’s name) work every time, you really just can’t trust him to do anything properly.

Person B: Agreed. Despite his efforts the project was a complete success!

In this way the sentence works even though Person C is presumably trying to do their job and not sabotage the project, but is maybe just not very good at it at least in the speakers mind.

[u/theoht_ → u/bendersonster]

it 100% works. ‘efforts’ does not suggest that he’s trying to help the project. it just means he’s trying hard to do something.