An activity base . is part of the organization where major operations are planned and carried out is sometimes called a cost driver measures whatever causes costs to vary is a measure of whatever causes fixed costs to occur

measures whatever causes costs to vary

is sometimes called a cost driver

Explanation:

Activity base is an action that is measured in activity based costing method. It is used to share overhead cost.

For example if cost of maintenance of machines is to be allocated to produced goods, machine hours is a good basis that is measured to achieve this.

In a more complex scenario several activity bases can be used to allocate cost.

So activity base measures whatever causes cost to vary and is also a cost driver

i think this is true i hope this

answer; i believe its (d) intrinsic;