Question

Fill in the blank with the right choice of word.
The assumption that chlorofluorocarbons would be ____ in the environment because they were chemically inert, was challenged by the demonstration of a potential threat to the ozone layer.
a- deleterious
b- innocuous
c- persistent
d- noxious
e- durable

Answer 1

Hint: The passage is trying to portray the idea that the assumption that chlorofluorocarbons would be non-poisonous in the environment because they were chemically inert, was challenged by the demonstration of a potential threat to the ozone layer.

Complete answer:
As given in the hint, we need to choose the word that fulfills the given idea.
The word, ‘innocuous’ refers to something that is not harmful or not poisonous. It was derived from the Latin word- Innocuous, which means not injurious.
Let’s look at its usage-
For example- The government didn’t bother about the innocuous gas leak. Here, we can understand that the government didn’t bother about the non-poisonous or non-toxic gas leak.
Now, let’s examine the given options-
Option a- ‘deleterious’ refers to something that is harmful or damaging to others. ‘Deleterious’ is the opposite in meaning to the given context. Hence, it is an incorrect option.
Option b- ‘innocuous’ refers to something that is non-poisonous or not harmful. ‘Innocuous’ is similar in meaning to the given context. Hence, it is the correct option.
Option c- ‘persistent’ refers to the action of being persevering or determined. ‘Persistent’ is different in meaning to the given context. Hence, it is an incorrect option.
Option d- ‘noxious’ refers to something that is toxic or poisonous. ‘Noxious’ is the opposite in meaning to the given context. Hence, it is an incorrect option.
Option e- ‘durable’ refers to something that long-lasting or tough. ‘Durable’ is different in meaning to the given context. Hence, it is an incorrect option. The correct answer is Option ‘b’.

Note:
 Some synonyms of ‘innocuous’ are; safe, edible, innocent, etc while some antonyms of ‘innocuous’ are; obnoxious, harmful, unsafe, etc.