Identify the segment in the sentence which contains a grammatical error.
I knew that something was amissed in the plan submitted by the supplier.

Correct option is A

Option (a) contains an error.
Explanation: The word "amissed" is incorrect. The correct word is "amiss". "Amiss" is an adjective, and there is no word like "amissed".
Correct sentence: I knew that something was amiss in the plan submitted by the supplier.
Grammatical Rule Used:
Adjectives do not take "-ed" endings. "Amiss" is already an adjective, meaning "wrong or out of place".
Example:
Incorrect: Something seems offed.
Correct: Something seems off.