How can I disagree with the respected learner and Marie-Hélène? But I must! D would be appropriate if the sentence were, "If it weren't for your help, we couldn't survive these hard times." Both the threat and survival are ongoing conditions, and not past events, like the accident in the question. Just because the conditional clause isn't past perfect doesn't mean it's not type 3; it's nevertheless a situation in the past. Just in case I'm wrong, is there a reference you could cite that makes your point? (If I'm wrong, then my wife is too, and that's really unlikely!) Thanks much

Hi I would say the answer is "D" for the same reasons above ...

'A' can be used only if we have 'If + past perfect'. In this case, we should use conditional type 3: If + past perfect... + would (or 'could' or 'should' or 'might') have + past participle = If you had helped us, we could have survived the accident. = If it had been for your help, we could have survived the accident. We use this type to express regret or reproach.

Answer D is certainly the correct answer! If + simple past... + would (or could or might) do If it weren't for your help, we couldn't survive the accident. = If you didn't help us, we couldn't survive the accident. Here the past tense expresses an unreal condition (something unreal). 'If it weren't for your help' means that 'really it is your help and that really you helped us', but I'm only imagining that you didn't help us.

A) we couldnt have survived!