*$_In a size reduction crushing operation, feed size is 300 to 1500 mm while the product size is 100 to 300 mm. This is a case of the __________ crushing.?

*$_In a size reduction crushing operation, feed size is 300 to 1500 mm

1.	*$_In a size reduction crushing operation, feed size is 300 to 1500 mm while the product size is 100 to 300 mm. This is a case of the __________ crushing.?
A.	Secondary
B.	Fine
C.	Primary
D.	Ultrafine
Answer» D. Ultrafine