Fill in the blank with the most appropriate preposition to complete the idiom. Virat Kohli added another feather _____ his cap by his wonderful performance in the one day international cricket match.

Introduction / Context:
In this English vocabulary question, you are tested on a common idiom that appears frequently in newspapers, sports commentary, and competitive exams. The expression is used in a sentence about Virat Kohli performing very well in a one day international cricket match. The task is to choose the correct preposition that completes the idiom and keeps the sentence grammatically correct and natural in standard English usage.

Given Data / Assumptions:
- The sentence contains the fixed idiom add another feather _____ his cap.
- We must choose a preposition from the given options in, to, on, into, and over.
- The intended meaning is that Virat Kohli achieved one more honour or distinction through his performance.

Concept / Approach:
In English, many idioms have fixed prepositions that do not change. One such idiom is feather in someone s cap, which means an additional honour, credit, or achievement that someone can be proud of. The verb add or gain is often used before this idiom. The standard pattern is add another feather to his cap. Therefore, the correct preposition is to. Other prepositions like in, on, into, and over may appear with other expressions, but they do not collocate with this idiom in natural English.

Step-by-Step Solution:
Step 1: Identify the idiom inside the sentence: feather _____ his cap.
Step 2: Recall the standard idiomatic expression, which is a feather in someone s cap, often used with add another feather to his cap.
Step 3: Check which preposition collocates correctly with the verb add and the idiom feather in his cap. The normal pattern is add a feather to his cap.
Step 4: Substitute to in the blank and read the full sentence to confirm that it is grammatically correct and idiomatically natural.

Verification / Alternative check:
If we consult standard English usage in dictionaries, grammar books, or trusted articles, the phrase is always given as a feather in someone s cap, and when describing the act of gaining such an honour we say add a feather to his cap. Reading the full sentence with to shows that the meaning becomes clear and the sentence sounds natural: Virat Kohli added another feather to his cap by his wonderful performance in the one day international cricket match.

Why Other Options Are Wrong:
- in: add another feather in his cap is not the standard form with add; in usually appears in the base idiom, not after add.
- on: add another feather on his cap is grammatically odd and not idiomatic.
- into: add another feather into his cap is incorrect because into suggests movement inside, which does not fit the metaphor.
- over: add another feather over his cap has no accepted idiomatic use in English in this context.

Common Pitfalls:
Many learners confuse the internal structure of idioms. They remember the phrase feather in his cap and incorrectly place in after added. However, when the verb add is used, the correct pattern is add something to something. Another common mistake is to overthink the physical image of a feather placed in a cap and choose in or on on that basis instead of relying on real language usage. Always remember that idioms must be learned as fixed chunks rather than assembled logically word by word.

Final Answer:
The correct preposition is to, so the complete sentence is: Virat Kohli added another feather to his cap by his wonderful performance in the one day international cricket match.