Under the U.S. Aids to Navigation System used on the Western Rivers, aids to navigation lights on the right descending bank show __________.

Correct Answer: Option B — white or green lights

On the Western Rivers, the right descending bank corresponds to the green (port) side of the channel for a vessel heading upstream. Consequently, lights on this bank show either green or white, as specified in the USCG Light List and 33 CFR 62.51.