Explanation:

The correct answer is Option 3: Both (A) and (B).

Under Section 161 of the Criminal Procedure Code (Cr. P.C.), a police officer conducting an investigation has the authority to examine any person acquainted with the facts or circumstances of the case. This allows the police to question individuals who may have relevant information. Additionally, the police officer is required to reduce the statements made by such persons into writing. This ensures that the information provided during the investigation is accurately documented, which helps in building the case and facilitating the legal proceedings. Both the examination and the written recording of statements are crucial for a thorough and fair investigation process.