At night, you are approaching another vessel and can see only her sternlight but neither of her sidelights. Under the Inland Rules, this situation is best described as which type of encounter?

Why C is correct

33 CFR §83.13(b) defines the overtaking situation as one in which the overtaking vessel, at night, would be able to see only the sternlight of the vessel ahead and neither of her sidelights. Seeing only the sternlight is the nighttime indicator of an overtaking situation.