Directions: Read the given passage and answer the questions that follow (Q.…
2016
Directions: Read the given passage and answer the questions that follow (Q. No. 78 to 84) by selecting the most appropriate option. Scientists are extremely concerned about the changes taking place in our climate. The changes are said to be alarmingly rapid and the result of human activity whereas in the past it had been natural and much slower. The major problem is that the planet appears to be warming up (global warming). This is occurring at a rate unprecedented in the last 10,000 years. The implications are very serious. Rising temperatures could give rise to extremely high increase in the incidence of floods and droughts, having effect on agriculture. It is thought that this unusual warming of the Earth has been caused by greenhouse gases, such as carbon dioxide, being emitted into the atmosphere by car engines and modern industrial processes. Such gases not only add to the pollution of the atmosphere, but trap the heat of the sun leading to the warming up of the planet. It has been suggested that industrialized countries would try to reduce the volume of greenhouse gas emissions and plant more trees to create 'sinks' to absorb greenhouse gases. 83. Greenhouse gases refer to:
- A.
emission of gases by the cars alone.
- B.
emission of gases by the industries alone.
- C.
trapping of heat of the sun by the earth increasing temperatures alone.
- D.
carbon dioxide being produced from any source.
Show answer & explanation
Correct answer: D
In a reading-comprehension 'refers-to' question drawn from a passage, the correct choice is the one option, among those offered, that carries no error against the passage's own wording: it must not add a restriction the text does not state (an absolute word like 'alone' or 'only' when the passage names more than one contributing source), and it must not substitute the term's effect for what the term itself denotes. Where none of the offered options is a verbatim restatement of the passage, the correct one is the single option that survives this elimination without either flaw.
The passage defines greenhouse gases directly: greenhouse gases, such as carbon dioxide, being emitted into the atmosphere by car engines and modern industrial processes. This sentence names carbon dioxide as the example gas and names two separate sources, car engines and industrial processes, for its emission, and only afterwards explains separately that such gases trap heat and warm the planet. So the passage defines the gases by what they are, carbon-dioxide-type gases, and deliberately leaves their origin open to more than one source, not to only one.
restricting the source to cars alone adds a restriction ('alone') that the passage's own sentence does not support, since it names industrial processes as a further contributing source in the same breath.
restricting the source to industries alone adds the same kind of unsupported restriction, since the passage also names car engines as a contributing source.
describing the trapping of heat that raises temperatures names what these gases do once already in the atmosphere, the warming effect explained in the next sentence, not what the gases themselves are.
carbon dioxide produced from any source carries neither flaw: it does not add an 'alone'/'only' restriction the passage does not support, and it does not substitute the gases' heating effect for what the gases are; among the four options offered, it is the only one free of a disqualifying error, even though the phrase 'any source' is a generalisation beyond the two sources the passage names rather than a verbatim restatement of the text.
Because the first two options each add an unsupported 'alone' restriction and the third substitutes the heating effect for the definition, and because the fourth carries neither flaw, it is the best-supported choice among the options actually offered: the passage's own two named sources rule out an 'alone' restriction, and its own separation of cause from effect rules out the heat-trapping description.