Question

Assertion: Agricultural output increased several times after the introduction of DDT.
Reason: DDT was the first insecticide used on a wide scale
(A) Both Assertion and Reason are correct and the Reason is the correct explanation for Assertion.
(B) Both Assertion and Reason are correct but the Reason is not the correct explanation for Assertion.
(C) Assertion is correct Reason is incorrect.
(D) Both Assertion and Reason are incorrect.

Answer 1

Agriculture has been a major part of human history. Production of crops and domestication of livestock has been a part of the agricultural industry. One of the major problems concerning this industry is the presence of insects and pests that hamper crop production. Insecticides and pesticides were used to combat this problem.

Complete answer:
One of the first chemically synthesized insecticides was dichlorodiphenyltrichloroethane also known as DDT. Othmar Zeidler, a chemist, was the person who first synthesized this compound. Another chemist Paul Hermann Muller received a Nobel Prize in Physiology or Medicine for discovering DDT‘s insecticidal properties. It attacked the nervous system of the insects. The compound was used against insects that cause malaria (mosquitos) and typhus. It was used during the Second World War.
Seeing its success in curbing insects, countries like the US made DDT available to the general public to be used as a household insecticide and in agricultural fields. DDT soon was produced on a large scale and used in many countries all around the world. It was an instant success and helped increase agricultural output in places ridden with insects.
Apart from being effective, this insecticide/ pesticide had a relatively low manufacturing cost. Because it stayed in the environment for a longer period, continuous spraying was not required.

The correct option is (A), Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.

Note: In 1972, the US banned the use of DDT in agricultural industries. In the Stockholm convention, a worldwide ban of DDT was called for. This was because of the detrimental impact the insecticide had on the environment as well as people. DDT stays in the environment for a long period and does not degrade easily. Biomagnification of the compound is also a problem. The compound starts accumulating in every trophic level of the food chain. People who got exposed to the chemical experienced nausea, dizziness, fatigue, etc. Many insects also developed resistance to the compound.