Concerning the proper lubrication of a ring-oiled line shaft bearing, what statement is true?

Correct Answer: Option C — The oil level should be high enough so that the oiling rings dip into the oil, and the rings must freely rotate with the shaft.

Ring-oiled bearings rely on the rotation of the shaft to drive the oiling rings. The oil level must be sufficient for the rings to dip into the reservoir, but they must rotate freely with the shaft to continuously carry oil to the top of the bearing journal for lubrication.