Convert the following direct speech into indirect speech by choosing the most appropriate option: The old man said, "Thanks, I shall never forget this kindness, Ankit."

Introduction / Context:
This question tests your ability to change a sentence from direct speech to indirect speech. The original sentence shows an old man expressing gratitude to Ankit and adding a promise that he will never forget the kindness. To convert it correctly, you must change the reporting verb, adjust the pronouns and tenses, and preserve both the thanks and the assurance in a clear and natural indirect form.

Given Data / Assumptions:
- Direct speech: The old man said, Thanks, I shall never forget this kindness, Ankit.
- The speaker is the old man and the listener is Ankit.
- The message contains two parts: a thank you and a promise never to forget the kindness.
- We must choose the option that reports both elements accurately in indirect speech.

Concept / Approach:
In reported speech, the reporting verb said often changes to a more specific verb like thanked when the content of the speech is clearly an expression of gratitude. Also, when converting from shall in direct speech to indirect speech, with a third person subject, we generally use would. The pronoun I in direct speech refers to the old man, so in indirect speech it becomes he. The word this, referring to the kindness just experienced, becomes that in indirect speech. A correct answer should therefore read that the old man thanked Ankit and assured him that he would never forget his kindness.

Step-by-Step Solution:
Step 1: Replace the reporting verb said with thanked, which accurately reflects the act of expressing gratitude.
Step 2: Transform the sentence I shall never forget this kindness into he would never forget his kindness, changing I to he, shall to would, and this to his or that, depending on the structure.
Step 3: Join the two ideas by adding assured him that to report the promise part of the speech.
Step 4: Check the option that contains all these elements in a clear and grammatically correct indirect form.

Verification / Alternative check:
Option B reads: The old man thanked Ankit and assured him that he would never forget his kindness. This version correctly captures the act of thanking, uses assured to convey the promise, and applies the standard tense change from shall to would in reported speech. It also maintains correct pronoun reference, with he referring to the old man and him to Ankit. No other option includes both the thanks and the assurance in such an accurate and complete way.

Why Other Options Are Wrong:
- The old man applauded Ankit for his kindness and he shall never forget Ankit: applauded is not the right verb for giving thanks, and the clause he shall never forget Ankit changes the meaning from gratitude for kindness to not forgetting the person, which is different.
- Ankit was being thanked by the old man for his kindness towards an old man: this passive construction is clumsy and fails to express the promise about never forgetting the kindness.
- The old man said thank you to Ankit for his kindness: this reports the thanks but omits the assurance that he would never forget the kindness.
- The old man told Ankit that thanks would never be forgotten: this is awkward and changes the focus from the old man s memory to an abstract thanks, losing the original sense.

Common Pitfalls:
Students often focus only on the first part of the direct speech and ignore additional clauses such as promises or threats. In such questions, always identify all components of the original message and ensure that the chosen indirect speech option preserves them. Also, be careful with pronoun and tense changes. The form shall in direct speech very often becomes would when reported, especially with first or third person subjects in past reporting.

Final Answer:
The correct indirect speech is: The old man thanked Ankit and assured him that he would never forget his kindness.