Step 1: Understanding the Question:
This question asks us to identify the correct conversion of a declarative direct speech sentence into indirect speech.
The direct sentence is: ``Ravi said, 'I have completed my assignment.' ''
We must apply standard narration rules regarding tense backshifting and pronoun modification.
Step 2: Detailed Explanation:
1. Let us examine the components of the direct speech:
- Reporting verb: ``said'' (which is in the simple past tense).
- Conjunction: Since the reported speech is an assertive/declarative sentence, we use the conjunction ``that'' to connect the reporting clause and the reported clause.
2. When the reporting verb is in the past tense, the tense of the verb in the reported speech must shift backward:
- The verb in direct speech is ``have completed'', which is in the present perfect tense.
- According to grammar rules, the present perfect tense changes to the past perfect tense in indirect speech.
- Therefore, ``have completed'' must become ``had completed''.
3. Next, we must change the pronouns according to the speaker's perspective:
- The first-person subject pronoun ``I'' refers to the speaker ``Ravi''. Since Ravi is male, ``I'' changes to the third-person singular pronoun ``he''.
- The possessive determiner ``my'' changes to the corresponding third-person possessive determiner ``his''.
4. Combining all these changes, we get: ``Ravi said that he had completed his assignment.''
5. Let us evaluate the options:
- Option (A) ``Ravi said that he has completed his assignment.'' is incorrect because it retains the present perfect tense ``has completed'' instead of backshifting it.
- Option (B) ``Ravi said that he had completed his assignment.'' is correct as it properly implements both pronoun and tense shifts.
- Option (C) ``Ravi said that I had completed my assignment.'' is incorrect because it fails to change the pronouns ``I'' and ``my'' to the third person.
- Option (D) ``Ravi said that he completed his assignment.'' is incorrect because it converts the present perfect tense to the simple past tense ``completed'' instead of the past perfect tense.
Step 3: Final Answer:
Therefore, the correct option is (B).