Which of the Following Statements Concerning Cost Drivers Is Incorrect

Which of the following statements concerning cost drivers is incorrect?

A) Inaccurate application of overhead to products can lead to wrong conclusions about which products are profitable.
B) As direct labour shrinks as a proportion of manufacturing costs it becomes a more accurate factor by which to apply overhead to products.
C) A cost driver is a measure of the activity that causes overhead costs.
D) In modern day manufacturing there has been a decline in labour costs and an increase in factory overheads as a percentage of product costs.