In the following question, a sentence has been given in Direct speech. Out of the four alternatives, select the option that best expresses the same sentence in Indirect speech:\n\nThe trainee asked his boss, "Shall I email this letter again, Sir?"

Introduction / Context:
This question checks your understanding of changing Direct speech into Indirect (or Reported) speech, especially when the original question uses shall and is a polite offer or suggestion. The original sentence shows a trainee speaking respectfully to his boss and asking whether he should repeat an action. In Indirect speech, you must adjust the tense, pronouns, and demonstratives correctly, and also convert the question into a statement form after the reporting verb asked.

Given Data / Assumptions:

• Direct speech: The trainee asked his boss, "Shall I email this letter again, Sir?"
• Reporting verb: asked, which is in the simple past tense.
• Speaker: the trainee; listener: his boss.
• Pronoun I refers to the trainee, so it changes to he.
• Demonstrative this changes to that in Indirect speech.
• The question is about what the trainee should do in the future, not about a routine fact.

Concept / Approach:
When changing yes or no questions from Direct to Indirect speech, we use if or whether and change the word order to statement order. For questions starting with shall I that express offers or requests, we usually change shall to should in Indirect speech to show asking for advice or permission. Since the reporting verb asked is in the past, we also adjust deictic words like this to that. The respectful term Sir is usually dropped in Indirect speech and replaced by an adverb such as politely if needed.

Step-by-Step Solution:
Step 1: Keep the reporting clause in the same tense: The trainee politely asked his boss. Step 2: Introduce the connector if to report the yes or no type question. Step 3: Change I to he because the trainee is now referred to in the third person. Step 4: Change shall to should to express a polite request for guidance in Indirect speech. Step 5: Change this letter to that letter to match the normal shift in demonstratives. Step 6: Remove the direct form of address Sir and optionally carry its polite sense in the adverb politely.

Verification / Alternative check:
The resulting Indirect sentence is: The trainee politely asked his boss if he should email that letter again. If you convert this back into Direct speech, you can get a natural version of the original question: The trainee asked his boss, "Sir, shall I email this letter again?" The meaning is the same and the politeness is preserved. The grammar is also correct, with if introducing the reported question and should expressing the sense of shall I.

Why Other Options Are Wrong:
Option B uses shall in the reported clause, which is not standard when the reporting verb is in the past and when we are expressing a polite suggestion. Option C uses this letter and keeps sir in lower case at the end, which is awkward and does not fully follow the usual changes from Direct to Indirect speech; it also omits should for the advice meaning. Option D again uses shall and does not include any marker of politeness, and it also lacks the adverb that carries the tone of the original address Sir.

Common Pitfalls:
Students often forget to change shall to should when the meaning is asking for advice or making a polite offer. Another frequent mistake is to leave this unchanged when the context clearly requires that. Many learners also keep the question order (shall he email) instead of converting it into statement order (he should email). Remember that reported questions generally use normal subject verb order and that polite direct address words like Sir or Madam are usually removed or paraphrased.

Final Answer:
The best Indirect speech form is The trainee politely asked his boss if he should email that letter again.