Step 1: Understanding the Concept:
The question directly asks about the subject matter of Section 6 of the Code of Criminal Procedure (Cr.P.C.). The Cr.P.C. establishes the hierarchy and types of criminal courts that function in India.
Step 2: Detailed Explanation:
Section 6 of the Cr.P.C. is titled "Classes of Criminal Courts". It states that besides the High Courts and the courts constituted under any law other than this Code, there shall be in every State the following classes of Criminal Courts, namely:
(i) Courts of Session;
(ii) Judicial Magistrates of the first class and, in any metropolitan area, Metropolitan Magistrates;
(iii) Judicial Magistrates of the second class; and
(iv) Executive Magistrates.
This section forms the foundation of the criminal judicial structure in the country. Options B, C, and D are incorrect as the Cr.P.C. deals with criminal courts, not district, municipal, or civil courts specifically in this section.
Step 3: Final Answer:
Section 6 of the Cr.P.C. explicitly lists the "Classes of Criminal Courts". Therefore, option (A) is the correct answer.