Concept: Public Library Acts are important in the development of public library services because they provide legal support for establishing, maintaining and funding public libraries.
Step 1: Understanding the Mysore Public Libraries Act.
The Mysore Public Libraries Act was an important legislation for public library development in the state.
\[
\text{Public Library Act} \Rightarrow \text{Legal foundation for public libraries}
\]
Step 2: Identifying the date of enforcement.
The Mysore Public Libraries Act came into force on:
\[
22\ April,\ 1965
\]
Step 3: Choosing the correct option.
Among the options, April 22, 1965 matches the correct date.
Therefore, the correct answer is option (C).