Which of the following statements is true? moraines form when glaciers pick up large rocks. plucking happens when glaciers deposit rock and sediment. since 1979, the polar ice caps have grown in size about 20%. older glaciers have longer ice crystals than younger ones.

Moraines form when glaciers pick up large rocks.

Moraines are accumulations of stones, large rocks and sediments carried and transferred by a retreating glacier. A moraine is deposited as a ridge formed at the direction parallel to the ice movement.

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

instead of copying and pasting things off of tests or work done on computer which im sure you did, try and read over the question carefully