问题：

[单选] A new ocean going ship of 2000 gross tons having an inoperative oily water separator may dispose of its bilge slops by （）.

A . holding its slops onboard until they can be pumped into the city sewer system
B . circulating them through the lube oil purifier to remove water and debris
C . holding its slops onboard until they can be discharged to a shore side reception facility
D . pumping them into a settling tank for separation before pumping the oily water residue overboard