Consolidated Yarns and Knits produces knitted jersey fabrics and two of their products are produced in their Entenhausen facility. These two fabrics are of identical construction, but they are made from different yarns: one is made from a den 100 f 24 polyester yarn, the other from a den 100 f 23 Kevlar yarn. The Kevlar yarn is quite abrasive, causing knitting needles to wear out much faster. This results in higher downtime, more maintenance time for changing the needles, and higher auxiliaries costs for replacing needles. Downtime, maintenance cost, and auxiliaries are considered manufacturing overhead in this plant, and the total cost for these items in the plant is $18,000 each month. The following information is known about the products:

Product	Sets of Needles	Maintenance Hours	Preventive Cleanings	Monthly Production
Polyester Knit	5	80	10	250,000 yd.
Kevlar Knit	20	240	5	200,000 yd.
Cost per pool	$5000.00	$10,000.00	$3000.00

Being open-minded and flexible, the management in the plant decides to introduce an activity based costing system and use cost drivers to allocate the overhead costs for the three cost pools. What cost driver or activity driver should they use for the cost pool Cleaning Cost?

Select one:

a. Machine hours.

b. Number of needle sets.

c. Number of cleanings.

d. Direct labor cost.

e. Yardage (monthly production).