Fly to location marker i. The crests of these dunes are situated parallel to the prevailing wind direction. What kind of dune is this, and what is the prevailing wind direction?
a) Barchan dune; prevailing wind direction: perpendicular to the crest.
b) Longitudinal dune; prevailing wind direction: parallel to the crest.
c) Transverse dune; prevailing wind direction: perpendicular to the crest.
d) Star dune; prevailing wind direction: erratic.