The blank requires a word to indicate the restriction on the act of smoking in a given area. Among the options, 'allowed' (let (someone) have or do something), 'permitted' (officially allow (someone) to do something) and 'continued' (persist in an activity or process) are opposite to the context of the given sentence and thus they are negated. 'Escalated' (increase rapidly) is a contextually irrelevant and so it is also negated. Option (c) 'prohibited' (formally forbid (something) by law, rule, or other authority)is the most appropriate option that can fill the given blank as required and also match the context of the sentence.
Hence, the correct answer is option (c).
Note:
Qualifiers: A word or phrase that limits the meaning of another word or phrase or makes it less general. 'Adverbs' and 'adjectives' are qualifiers.
Study Notes
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