Read the given passage carefully and answer the questions that follow.
There is a fairly universal sentiment that the use of nuclear weapons is clearly contrary to morality and that its production probably so, does not go far enough. These activities are not only opposed to morality but also to law if the legal objection can be added to the moral, the argument against the use and the manufacture of these weapons will considerably be reinforced. Now the time is ripe to evaluate the responsibility of scientists who knowingly use their expertise for the construction of such weapons, which has deleterious effect on mankind.
To this must be added the fact that more than 50 percent of the skilled scientific manpower in the world is now engaged in the armaments industry. How appropriate it is that all this valuable skill should be devoted to the manufacture of weapons of death in a world of poverty is a question that must touch the scientific conscience.
A meeting of biologists on the Long-Term Worldwide Biological consequences of nuclear war added frightening dimension to those forecasts. Its report suggested that the long biological effects resulting from climatic changes may at least be as serious as the immediate ones. Sub-freezing temperatures, low light levels, and high doses of ionizing and ultraviolet radiation extending for many months after a large-scale nuclear war could destroy the biological support system of civilization, at least in the Northern Hemisphere. Productivity in natural and agricultural ecosystems could be severely restricted for a year or more. Post war survivors would face starvation as well as freezing conditions in the dark and be exposed to near lethal doses of radiation. If, as now seems possible, the Southern Hemisphere were affected also, global disruption of the biosphere could ensue. In any event, there would be severe consequences, even in the areas not affected directly, because of the interdependence of the world economy. In either case the extinction of a large fraction of the earth’s animals, plants and microorganism seems possible.
The population size of Homo sapiens conceivably could be reduced to prehistoric levels or below, and extinction of the human species itself cannot be excluded.
Choose the word, which is most opposite in meaning of the word in the passage Deleterious.
'Deleterious' means harmful often in a subtle or unexpected way. 'Beneficial', in the option is the correct opposite.