English Grammar — Spot the error (choose the incorrect part; select 'No error' if the sentence is correct). Sentence parts: A) Immediately after boarding the bus, B) Mahesh asked the conductor. C) that if he knew D) where the museum was, E) No error

Introduction / Context:
This sentence tests reported speech structure and conjunction choice after reporting verbs such as “ask.” The clash “that if” is ungrammatical in standard English in this context.

Given Data / Assumptions:

• Reporting clause: “Mahesh asked the conductor …”
• Embedded question about knowledge: “if he knew where the museum was.”
• Presence of “that if” indicates redundant complementizers.

Concept / Approach:
After “ask,” use “if” or “whether” for yes/no indirect questions, not “that.” The sequence should be “asked … if he knew where …” A full stop after “conductor” is also stylistically awkward mid-sentence, but the principal grammatical error tested is the “that if” combination in Segment C.

Step-by-Step Solution:

Verification / Alternative check:
Try “Mahesh asked the conductor whether he knew where the museum was.” The clause is now smooth and grammatical.

Why Other Options Are Wrong:

• A: Proper introductory adverbial phrase with comma.
• B: The period is stylistically off but the grammatical core error targeted is in C; typical tests expect exactly one grammatical error.
• D: “where the museum was” is well-formed for backshifted reported speech.
• E: Not applicable since C has an error.

Common Pitfalls:
Stacking complementizers like “that if” is a common learner error. Remember: after “ask,” select “if” or “whether” alone for yes/no content questions.

Final Answer:
C) that if he knew