单项选择题

When fuel oil is accidentally missed with lube oil which of the following processes can be used to separate them?()
Ⅰ.filtering
Ⅱ.settling

A.Ⅰ only
B.Ⅱ only
C.either Ⅰ or Ⅱ
D.neither Ⅰ or Ⅱ