In the following sentence improvement question, choose the correct prepositional phrase to replace the underlined part or select the no improvement option: The Vice Chancellor congratulated the blind student for his success in the examination.

Introduction / Context:
This question tests knowledge of prepositions used with the verb congratulate. In English, certain verbs form fixed combinations with particular prepositions, known as collocations. The common and correct expression is congratulate someone on something. Exams frequently present slightly incorrect prepositions such as for, in, or over to check whether candidates recognise the correct combination in standard usage.

Given Data / Assumptions:

The base sentence is: The Vice Chancellor congratulated the blind student for his success in the examination.

The underlined part involves the preposition and the object of congratulations.

We must choose the best version of this phrase, or decide that no change is needed.

All options preserve the general meaning but vary in prepositions or structure.

The context is formal academic communication.

Concept / Approach:

In standard English, the usual pattern is congratulate someone on something, not congratulate someone for something when referring to achievements or success. Therefore, we must look for the option that uses on in the correct position. In, for, and over either sound unidiomatic or have different nuances. We also need to ensure that there is no unnecessary preposition after congratulate, such as congratulate to, which would be grammatically wrong. The goal is to pick the sentence which a proficient speaker would naturally use in formal speech or writing.

Step-by-Step Solution:
Step 1: Review the original sentence: The Vice Chancellor congratulated the blind student for his success in the examination. Step 2: Recall the collocation congratulate someone on something for achievements like success, promotion, or good results. Step 3: Examine option a: congratulated the blind student in his success in the examination. The preposition in is incorrect here; we do not say congratulate in success. Step 4: Examine option b: congratulated the blind student on his success in the examination. This matches the standard collocation congratulate on and sounds natural. Step 5: Examine option c: congratulated to the blind student for his success in the examination. The addition of to after congratulated is wrong; we do not say congratulate to someone. Step 6: Examine option d: No improvement is needed. This would keep for his success, which is less correct for formal exam English. Step 7: Examine option e: congratulated the blind student over his success in the examination. Over is sometimes used in casual speech, but on is preferred and more standard in exam contexts. Step 8: Choose option b as the best and most accepted form.

Verification / Alternative check:

We can cross check with familiar examples: The teacher congratulated her on her excellent marks, They congratulated him on his promotion, and I congratulated them on their marriage. In each case, the preposition on links the verb congratulate with the achievement. This confirms that on his success is the correct phrase here, and that a change from for to on is required.

Why Other Options Are Wrong:

Option a uses in his success, which is not idiomatic with congratulate.

Option c adds to after congratulated, which is grammatically wrong in this pattern.

Option d suggests no improvement, but the current use of for does not match the most accepted form with this verb.

Option e uses over his success, which is less common and sounds awkward compared to the standard on his success.

Common Pitfalls:

Many learners confuse congratulate someone for something and congratulate someone on something because for is used with thank and blame. While congratulate for is occasionally heard, the form congratulate on is the established exam standard. To avoid mistakes, it is useful to memorise expressions like congratulate on success, condole with someone, and comment on something as fixed groups.

Final Answer:

The improved and grammatically standard sentence is: The Vice Chancellor congratulated the blind student on his success in the examination.