A bit that is turned off represents the following value: . a. binary numbering
b. ASCII
c. Unicode
d. ENIAC

a. binary numbering

Explanation:

In Computer science, a bit is a short word for the term binary digit and is primarily the basic (smallest) unit measurement of data or information.

A bit is a logical state which represents a single binary value of either one (1) or zero (0). This ultimately implies that, a single bit in computer science represents a boolean value of;

1. True or ON, which is equal to one (1).

2. False or OFF, which is equal to zero (0).

Hence, a bit that is turned off represents the value of binary numbering because it has a numerical value of zero (0).

Additionally, a binary numbering represents all numeric values that are to be written in sequences of ones (1s) and zeroes (0s).