Name of rightmost bit – UGC NET Question

In a binary number, the rightmost bit represents the smallest positional value, 2^0 or 1. Because it contributes the least weight to the overall number, it is called the least significant bit (LSB). This bit is important in operations like parity checking and incrementing. Therefore, the term least significant correctly describes the rightmost bit.

Option A:
Option A names the "most significant" bit, which actually refers to the leftmost bit that has the highest positional value. It denotes the largest weight in the number and is not located on the right. Hence this cannot describe the rightmost bit.

Option B:
Option B is correct because the rightmost bit carries the smallest positional weight and so is least significant. In many algorithms, changes in the LSB affect the number by one unit, reinforcing its role as the least significant bit. This terminology is standard in digital electronics.

Option C:
Option C refers to a "control" bit, which is not a standard name for the rightmost position. Control bits can appear in various positions depending on the protocol or format; they are not inherently tied to the rightmost place.

Option D:
Option D suggests a "status" bit, which is a general term for bits that signal conditions but not necessarily the rightmost one. Status indicators may reside anywhere in a control word or register.