Official Solution:

The latest investigation proves that either the building-owner or his tenants are to be accounted for yesterday’s fire that burnt as long as or longer than four hours.

A. to be accounted for yesterday’s fire that burnt as long as or longer than
B. accounted for yesterday’s fire, which burnt at least as long as
C. held accountable for yesterday’s fire, which burnt longer or as long as
D. accountable for yesterday’s fire, which burnt at least as long as
E. to be held accountable for yesterday’s fire that burnt longer than or at least as long as


A. The idiom accountable for, not accounted for, is used to mean responsible for . The phrase as long as or longer than is unnecessarily wordy and awkward.

B. The idiom accounted for is incorrect.

C. To hold someone accountable for something means to consider someone responsible for something. The investigation proves that someone is accountable for the fire. The investigation is not meant to prove that someone is held accountable for the fire.

than is missing for the comparative adjective longer. Even with the than, the phrase would be wordy.
Correct.
D. The idiom accountable for is correctly used. The phrase at least as long as presents the intended meaning most economically.

E. The phrase longer than and at least as long as are redundant.


Answer: D
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As per the explanation provided for option C, am i right in understanding that the meaning of the sentence changes entirely by using the word "held accountable"?

secondly, if the answer to my first query was affirmative, then even option e can be rejected for similar reason. Right?

Third, in gmat exam how is possible to infer the correct meaning of the sentence. Any tip to make it easy?

1. Yes

2. Right.

3. It has not been mentioned in any official guideline that the correct answer must retain the meaning of the original sentence. If there is only one grammatically correct choice, it must be selected even when it deviates in meaning from the original. However if there are two grammatically correct sentences, select the one that agrees with the intended meaning of the original sentence.

I am note sure why B is wrong. as far as i know "accounted for" isn't an incorrect idiom. D sounds good, but need to be clear...
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The phrase " X is accounted for" is used to mean that it is known where X is or what happened to X. e.g., After the earthquake, 10 of the inhabitants could not be accounted for. This usage is inappropriate here.


The phrase "held accountable for" means "held responsible for". This meaning is correct in this context.

how, account for also means responsible for as i know..?

Isn't the subject " tenants' missing 'verb' in choice D ?