Framing the Correct Question for a Given Answer

The task is to identify the correct question that matches the provided answer: "He has gone to the railway station to see off his cousin." The question structure is given as "Why __________ ?". We need to fill in the blank correctly.

Understanding the Answer's Tense and Context

The provided answer, "He has gone to the railway station to see off his cousin," uses the present perfect tense ("has gone"). This tense is used for actions completed in the past that have relevance to the present. The question needs to ask for the reason ('Why') behind this specific action.

Evaluating the Question Options

Let's examine each option to determine grammatical correctness and appropriateness:

1. Option 1: $Why has he gone to the railway station?$

   Grammar & Tense: This question uses the present perfect tense ('has gone') correctly. The structure follows the standard interrogative form for this tense: Auxiliary verb ('has') + Subject ('he') + Past Participle ('gone').

   Relevance: It directly asks for the reason ('Why') for the action described in the present perfect tense, perfectly aligning with the provided answer.

   Verdict: Grammatically correct and contextually suitable.

2. Option 2: $Why he went to the railway station?$

   Grammar & Tense: This phrasing is grammatically incomplete as a question. The standard interrogative form for the simple past tense is 'Why did he go...?'. Also, it uses the simple past tense ('went'), which doesn't match the present perfect tense of the answer.

   Verdict: Incorrect grammar and tense mismatch.

3. Option 3: $Why he go to the railway station?$

   Grammar & Tense: This is grammatically incorrect. A present simple question would require 'does' ('Why does he go...?'), and a past simple question would require 'did' ('Why did he go...?').

   Verdict: Fundamentally incorrect sentence structure.

4. Option 4: $Why have he gone to the railway station?$

   Grammar & Tense: This option contains a subject-auxiliary verb agreement error. The third-person singular subject 'he' requires the auxiliary verb 'has', not 'have'.

   Verdict: Grammatical error in subject-auxiliary verb agreement.

Conclusion on the Correct Question

Based on the grammatical analysis and tense consistency, Option 1, "Why has he gone to the railway station?", is the only question that correctly prompts the given answer. It adheres to proper English grammar and effectively asks for the reason behind the action stated in the answer.