In the following question, a sentence is given in Indirect speech. Choose the option that best expresses the same idea in Direct speech. He said that when he was a boy he could stay up as long as he liked.

Introduction / Context:
This question checks the ability to reconstruct a past time narrative in Direct speech from its Indirect form. The speaker is recalling his childhood and his ability to stay awake as long as he wished. Learners must keep the past time setting and the modal "could", while restoring the original pronouns and natural English word order inside the quotation marks.

Given Data / Assumptions:

• Indirect speech: He said that when he was a boy he could stay up as long as he liked.
• The reporting verb "said" is in simple past and has no object.
• The clause "when he was a boy" sets a past time frame.
• The modal "could stay up" expresses ability during that past period.
• The statement describes a repeated or general ability, not a single event.

Concept / Approach:
When converting back to Direct speech, we usually replace the third person pronoun "he" with "I" because the original speaker is talking about himself. The time clause "when he was a boy" becomes "When I was a boy". The modal "could" remains "could" in Direct speech because it is the natural past form relative to the boyhood stage. The reporting verb "said" remains outside the quotation marks with a comma. No change to "as long as he liked" is necessary except pronoun alignment to "as long as I liked".

Step-by-Step Solution:

Verification / Alternative check:
The resulting Direct speech sentence is natural and grammatical. It clearly presents a recollection of childhood from the speaker's perspective. The time clause and the expression of ability are both correctly expressed in past forms. The quotation matches how an English speaker would typically talk about their own boyhood habits.

Why Other Options Are Wrong:
Option A uses "had been a boy" which is an unnecessary past perfect and sounds unnatural for a general statement about childhood. Option B incorrectly uses "told" without an object, which is grammatically wrong, because "told" needs someone to be told. Option D changes the time frame to "When I am a boy I can stay up as long as I like", which shifts the meaning to a present time and is logically incorrect. Option C correctly matches the tense and structure, and only needs the small implicit change of "he liked" to "I liked", which is already present in the option.

Common Pitfalls:
A common mistake is to overuse past perfect when it is not required, leading to sentences like "When I had been a boy". Another difficulty is confusing "could" with "can" when talking about general past abilities. Remember that "could" is the usual modal for past ability, and it often remains unchanged when going between Direct and Indirect speech if the time frame is clearly in the past.

Final Answer:
The correct Direct speech form is He said, "When I was a boy I could stay up as long as I liked."