Answer:
B: sand sea
Explanation:
"Erg" is an acronym used to describe a sand sea that, in general, refers to a mountain of sand that was created by the wind in a flat area. The dunes do not have any vegetation cover, since the wind can only drag the sand. In addition to the sand sea, the acronym "erg" can indicate the existence of sand sheets, which are created when the dunes are not formed.
