Choose the right option of indirect speech:

He said, "The country passed through a crisis ten years ago."

Option B is the correct answer.

When transforming direct speech to indirect speech, you typically shift the verb tenses back one step in time, especially when reporting something that occurred in the past.

In the original direct speech, "passed" is in the past tense. When converting it to indirect speech, we shift the tense of the verb "passed" to its past perfect form "had passed" to indicate that the crisis occurred before the time of the reporting.

So, "ten years ago" becomes "ten years before" to maintain the same relative time frame. Therefore, the correct indirect speech version is:

b) He said that the country had passed through a crisis ten years before.