Explanation:

- Section 162 of the Code of Criminal Procedure, 1973: It deals with the use of statements made to police during an investigation. These statements cannot be used as evidence in trial unless covered by certain exceptions, mainly to protect fair trial rights.

- Option 1: Accused: This section indirectly protects the accused by preventing statements made to police from being used against them during trial.

- Option 2: Witnesses: Also protects witnesses as their statements to police are not evidence until made in court.

- Option 3: Police officer: Section does not directly protect police officers; it restricts the evidentiary value of statements made during their investigation.

- Option 4: Magistrate: It does not protect magistrates; it involves investigation procedures before a trial reaches them.

- Correct Answer: Option 1 - Accused