Assertion : Combine is the farm machine which is used for both harvesting and threshing.
Reason : After threshing, the grains have to be separated from the chaff.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

B

Explanation

Once the crop matures, it is harvested, i.e., cut and gathered. This may be done manually by using a sickle or by using a machine called harvester. Next, the grains are separated from the cut crops. This process is called threshing. Threshing can be done manually by making oxen or buffaloes trample over the cut crops or it can be done by a machine called thresher. However, a machine called combine is also used for both harvesting and threshing. After harvesting and threshing, winnowing has to be done to separate the grains from the chaff. It can be done manually with the help of wind. In this process, the mixture is dropped from a height. The heavier seeds fall almost vertically down, whereas the lighter chaff gets blown away by wind and falls at a distance. A winnowing machine is also used for this purpose.