Historians are unsure whether the Black Death, one of the most devastating events in recorded human history, actually affected population levels or not since these levels had already begun a gradual decline due to living conditions years before.
A. Historians are unsure
whether the Black Death, one of the most devastating events in recorded human history, actually affected population levels
or not -
"Weather or not" is unidiomatic and never used in GMATB. Historians are unsure whether the Black Death,
a most devastating event in recorded human history, actually affected population levels -
The most devastating event is the correct usageC. Historians are unsure whether the Black Death, one of the most devastating events in recorded human history, actually affected population levels -
Correct answerD. The Black Death is one of the most devastating events in recorded human history, but historians are unsure
if it actually affected population levels -
"If" is only used in conditionalsE. Historians are unsure whether the Black Death,
which is known to be one of the most devastating events in recorded human history, actually affected population levels -
which is known to be makes the sentence wordy