The correct answer is (c) Certiorari.
A writ of certiorari is a discretionary writ issued by a higher court to an inferior court to review a case. It is used to correct errors of law or to ensure that the inferior court has jurisdiction over the case.
A writ of quo warranto is a writ issued to inquire into the right of a person to hold a public office. It is used to challenge the legality of a person’s appointment to a public office.
A writ of mandamus is a writ issued to compel a public official to perform a legal duty. It is used to force a public official to take action that is required by law.
A writ of habeas corpus is a writ issued to bring a person before a court to determine whether they are being held lawfully. It is used to challenge the legality of a person’s detention.
In the case of the functioning of subordinate courts, a writ of certiorari is the most appropriate writ to use. This is because a writ of certiorari allows the higher court to review the decision of the subordinate court and to correct any errors of law that may have been made.