Name of leftmost bit – UGC NET Question

The leftmost bit in a binary number carries the largest positional weight because it corresponds to the highest power of 2 in the representation. This makes it the most significant bit (MSB). Its value greatly influences the magnitude of the entire number. Therefore, it is correctly referred to as the most significant bit.

Option A:
Option A labels it "low order," which is usually associated with bits near the right side that carry smaller weights. Using low-order terminology for the leftmost bit contradicts standard conventions in digital design.

Option B:
Option B suggests a parity bit, which is a special bit added to detect errors. A parity bit may be placed at either end of a word and is not inherently the leftmost data bit. Thus, parity does not define the leftmost bit of any binary number.

Option C:
Option C is correct because the leftmost bit has the greatest influence on the numeric value and is therefore called the most significant. In signed representations, this bit may also indicate the sign of the number, reinforcing its significance.

Option D:
Option D uses the term "overflow" bit, which typically refers to a flag indicating arithmetic overflow in a status register. It is not a positional name for any particular bit within a numeric representation.