Assertion. A linear list refers to a named list of finite number of similar data elements.

Reason. Similar type of elements grouped under one name make a linear list.

(a)

Both Assertion and Reason are true and Reason is the correct explanation of Assertion.

Explanation
A linear list consists of a finite number of homogeneous data elements, i.e., data elements of the same data type, arranged in a sequential manner under one name.