Which of the following is important in accumulating and removing sand that result in shifting barrier islands?
a. rip currents
b. geostrophic currents
c. tides
d. longshore currents

D. Longshore currents

Explanation:

Longshore currents are characterized as the sediment transport that occurs in the surf zone, due to the oblique incidence of the waves, along the beach. A current develops between the beach and the surf zone parallel to the coast, normally between 0.3 and 1 m / s. It is this process that is responsible for accumulating and removing sand that results in displacement of barrier islands.

answer: 45

explanationyou have to add as well to be it could be

when it is at an intermediate population density