Explanation:

Remote processing and time-sharing capabilities were significantly introduced and became widespread during the Third Generation of computers (approximately 1965-1971). This generation, characterized by the use of Integrated Circuits (ICs), enabled the development of more sophisticated operating systems. These operating systems could manage multiple users and tasks concurrently, allowing users to interact with the computer from remote terminals and share the computer's resources efficiently through time-sharing. The (a) First and (b) Second generations primarily used batch processing, lacking widespread remote access or time-sharing. The (d) Fourth generation further refined these concepts with personal computers and networking. Therefore, the Third generation ($ \text{c} $) is when these concepts were introduced.