Question

there would have been a disaster, if the earthquake......... longer
A) lasted
B) had lasted
C) lasts
D) have lasted

Answer 1

the one is suppositional clause and in such case the dependent had lasted

i.e. had + verb ki third form use hoti hai

Answer 2

Option B is correct

Had lasted

Explanation:

• It's a third type of conditional sentence.
• In the first clause, if there is "would have been" used, the second clause must have a past perfect tense
• Like in the above sentence,  
• There would have been a disaster,
• So we will use past perfect tense in the second clause
• There would have been a disaster, if the earthquake had lasted long.

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20 grammar rules with examples​

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