Scientific research begins with the posing of a solvable problem. The next step is to offer a possible solution to the problem through a proposition that can be declared true or false. Therefore, the hypothesis is the testable proposition that may prove to be the solution of the problem. Based on this concept, we can say that in scientific research, the term "hypothesis" refers to the proposed explanation of the problem that the research wishes to solve.
The best answer is B. The river flooded yearly which allowed the fertile sediment on the bottom of the river to flow onto the farmland, keeping it fertile.
