Fact 1: When a river floods , that river deposits soil in flood plains. Fact 2: Plants grow in soil. Given the two facts above, what do flooding rivers help plants do?

Choose your answer from:
(1). growth.
(2). store.
(3). roots.
(4). health.
(5). grow.
(6). adapt.
(7). widen.
(8). expand.
The answer is:
(5).