Explanation:

The Central Processing Unit (CPU) is often called the "brain" of the computer because it performs the core tasks of executing instructions and processing data. Option (a) "carry out program instructions" is a primary function of the CPU, as it fetches, decodes, and executes instructions from programs. Option (c) "process data and information" is also a fundamental role, as the CPU performs calculations and logical operations on data. Since the CPU is responsible for both executing instructions and processing data, option (d) "both (a) and (c)" accurately encompasses its main jobs. Option (b) "store data/information for future use" is primarily the role of storage devices (like hard drives) and main memory, not the CPU itself.