Answer:
B.) Fifty percent of the pies have disappeared
Explanation:
For A, there would be no test after essay, and for C and D, has doesn’t fit, although have would.
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In the English language, the word "who" is almost always used as a pronoun.
It represents a person, similar to the words "I" and "me".
Answer:
Writers use literature to criticise or endorse social conditions, expressing their own opinions and viewpoints of the world they live in. ... This means that the writer's views and values are always open to interpretation, and possibly even controversial.