Which of the options below are correct descriptions of hard stabilization of beaches? Select all that apply. Which of the options below are correct descriptions of hard stabilization of beaches? Select all that apply. Groins, which are built in pairs at river entrances, aim to keep sand from depositing in the channel. Groins unfortunately cause longshore currents to erode sand from the beach on their downcurrent sides. Jetties, which are built in pairs at river entrances, aim to keep sand from depositing in the channel. An effect of jetties is the erosion of sand on their downcurrent sides and the deposition of sand on their upcurrent sides. Seawalls are built to reflect the forces of unspent waves on the seaward side. Unfortunately, seawalls cause erosion of the beach on the landward side. Groins, which are built to maintain or widen beaches, are barriers built at a right angle to the beach. Groins unfortunately cause longshore currents to erode sand from the beach on their downcurrent sides. Seawalls are built to reflect the forces of unspent waves on the seaward side. Unfortunately, seawalls cause erosion of the beach on the seaward side.