Topic: Antonyms, Subject: English Grammar (ইংরেজি গ্রামার)

Best Answer Explained in Below-:

The term "plethora" refers to an excessive amount or abundance of something, often implying that the quantity present is more than what might be needed or useful. When considering antonyms, we are looking for words that convey an opposite meaning. Among the provided options, "shortage" (D) stands out as the most fitting antonym for "plethora."

A "shortage" signifies a lack or deficiency in quantity, suggesting there is less than what is required. This directly contrasts with "plethora," which denotes an overwhelming excess. For instance, if one has a plethora of resources, it means they have far more than what they need, whereas a shortage of resources means there is not enough to meet demand.

The other options—"profusion," "current," and "balance"—do not serve as antonyms. "Profusion" is synonymous with "plethora," indicating abundance. "Current" relates to timeliness and does not pertain to quantity, while "balance" implies equanimity or equality rather than a comparison of abundance versus deficiency. Therefore, the correct choice, "shortage," effectively captures the idea of scarcity in stark contrast to the concept of abundance inherent in "plethora."