The sequence here according to me is

1. seeing the body – first act – so past perfect 'had seen' is necessary
2. Having no doubt – the second act- hence simple past is needed- 'had no doubt' is used in the sense of 'possessed no doubt'. – 'had' is used as the simple past of 'have'

So E is ok in the use of appropriate tenses.
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Friend
It cant be A

read it again and get the total picture
apart from TENSE issue
there is another Wrong COMPARISON ISSUE here
Once they had seen the report from the medical examiner, the investigators did not doubt whether the body recovered from the river was the man
the Body=the man


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Hi,

Just a basic question . The Sentence structure is Once X had (Past perfect)Y Happened (Past tense). Is "Had no Doubt" is a past tense or perfect tense?

Thanks in advance

The body .... was the man ! this's even nonsensical. It should be "the body .... was that of .."
A,B and C are out.
At the beginning of the sentence it says " Once they had seen that indicate that there is something happened before a simple past event. So, we need to use a simple past to make sense of the prompt.

Hi longhaul123, the structure of past perfect is:

had + past particiiple

Past particiiple of the verb doubt is doubted.

So, the past perfect tense of the verb doubt would be had doubted. Hence, had doubt is not past perfect.

Incidentally, the real source of confusion here is that in this sentence, doubt is not used as a verb, but as a noun.

When used as noun, following would be the various tense forms (note that have is the verb here):

I have a doubt.
- Present tense

I had a doubt.
- Past tense

I have had a doubt.
- Present perfect tense

I had had a doubt.
- Past Perfect

When doubt is used as a verb, following would be the various tense forms:

I doubt.
- Present tense

I doubted.
- Past tense

I have doubted.
- Present perfect tense

I had doubted.
- Past Perfect

The structures have had and had had are often a source of confusion for test-takers. Our book EducationAisle Sentence Correction Nirvana discusses have had and had had. Have attached the corresponding section of the book, for your reference.

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It should jump off the screen when we see the two different comparisons: "the body was the man" and "the body was that of the man", hence A, B, and C are out.

Once they had seen the report from the medical examiner, the investigators did not doubt whether the body recovered from the river was the man who had attempted to escape from the state prison.

(A) did not doubt whether the body recovered from the river was

(B) have no doubt whether the body recovered from the river was

(C) had not doubted that the body recovered from the river was

(D) have no doubt whether the body recovered from the river was that of - the past perfect tense in the beginning indicates that the verb "have" is incorrect;

(E) had no doubt that the body recovered from the river was that of - good