The following sentence has been split into four segments. Identify the segment that contains a grammatical error.
Please tell me the truth, / is he here to have been investigating / the murder that / happened across the street?

Correct option is A

The correct segment that contains a grammatical error is “is he here to have been investigating.”
Error identification: The phrase "to have been investigating" is incorrect in this context. The correct phrase should be "to investigate," which aligns with the purpose of being present.
Grammatical Rule used: Infinitives like "to investigate" are used to express the purpose of an action, not past actions like "have been investigating."
Corrected sentence: Please tell me the truth, is he here to investigate the murder that happened across the street?