The correct answer is: B. Logic gates
Logic gates are the building blocks of all the circuits in a computer. They are used to perform basic operations such as AND, OR, and NOT. Logic gates can be combined to create more complex circuits, such as adders, subtractors, and multipliers.
A circuit switch is a device that connects two or more circuits together. It is used to control the flow of data in a computer.
Logical operators are used to compare two values and return a Boolean value (true or false). They are not used to build circuits.
Instructions are the commands that a computer executes. They are not used to build circuits.
None of the above is the correct answer.