Convert the sentence from Direct to Indirect speech: Neha said, "Need I write a letter?" Choose the correct reported form.

Introduction / Context:
This question assesses your understanding of converting direct speech, especially questions, into indirect or reported speech. The original sentence uses a modal question beginning with "Need I". When reporting such a sentence, you must adjust the word order, pronouns, and sometimes the auxiliary verb, while keeping the sense of the question intact. The reporting verb "said" is typically changed to "asked" when a question is reported.

Given Data / Assumptions:
- Direct speech: Neha said, "Need I write a letter?"
- The speaker is Neha and she is asking a question about obligation.
- The reporting verb in indirect speech should reflect that a question was asked.
- The tense sequence usually shifts one step back when the reporting verb is in the past.

Concept / Approach:
In indirect speech, yes or no type questions often use "if" or "whether" to introduce the subordinate clause. "Need I write a letter?" essentially means "Do I have to write a letter?" or "Must I write a letter?". When converting this to reported speech with a past reporting verb, "Need I" changes to "she had to" in indirect form, since obligation expressed in the present often becomes past obligation in reported speech. The correct structure becomes "Neha asked if she had to write a letter."

Step-by-Step Solution:
Step 1: Change the reporting verb "said" to "asked" because she is asking a question. Step 2: Remove quotation marks and introduce the reported clause with "if". Step 3: Change the pronoun "I" to "she" to match the subject Neha. Step 4: Convert "Need I write" to its indirect equivalent. Present sense of obligation becomes "had to". Step 5: Combine everything to form "Neha asked if she had to write a letter."

Verification / Alternative check:
Examine the options: Option A uses "have to", which does not show the backshifting of tense after a past reporting verb. Option B converts it to a continuous form "had been writing", which changes the meaning from asking permission or obligation to talking about a past ongoing action. Option C, "asked of writing a letter", is grammatically incorrect and does not report a question properly. Only option D preserves the idea of obligation and follows correct indirect speech rules.

Why Other Options Are Wrong:
- Option A: "have to" maintains a present tense form, ignoring the usual tense backshift after a past reporting verb like "said".
- Option B: "had been writing" suggests that the action was already happening, which is not implied in the original question about obligation.
- Option C: The structure "asked of writing a letter" is incorrect and does not follow standard indirect question patterns.

Common Pitfalls:
Learners may forget that questions are turned into statements in indirect speech and must follow normal word order instead of inversion. Another frequent error is to ignore modal changes such as "must" to "had to" or "need I" to "had to". Always identify the function of the question first (here, asking whether she is required to write a letter) and then choose the reported form that keeps that function intact.

Final Answer:
The correct reported speech form is Neha asked if she had to write a letter.