The terminal count of a typical modulus-10 binary counter is 1001 (option C). This means that when the counter reaches its maximum count value, it will output the binary number 1001.

To understand why option C is the correct answer, let's break down the operation of a modulus-10 binary counter.

Modulus-10 Binary Counter:
A binary counter is a sequential circuit that cycles through a predefined sequence of binary values. The modulus-10 binary counter is designed to count from 0 to 9 and repeat. It uses four flip-flops to store the binary values.

Binary Representation:
In a binary system, each digit can have two possible states: 0 or 1. To represent the numbers from 0 to 9, we require four binary digits.

The binary representation of the numbers from 0 to 9 are:
0 - 0000
1 - 0001
2 - 0010
3 - 0011
4 - 0100
5 - 0101
6 - 0110
7 - 0111
8 - 1000
9 - 1001

Terminal Count:
The terminal count refers to the maximum count value that the counter can reach before it resets to zero and starts counting again. In the case of a modulus-10 binary counter, the terminal count is 9, which is represented in binary as 1001.

Explanation of Option C:
Option C, which is 1001, represents the binary equivalent of the terminal count of a modulus-10 binary counter. When the counter reaches its maximum count of 9, it will output the binary number 1001.

Therefore, option C (1001) is the correct answer for the terminal count of a typical modulus-10 binary counter.

In summary:
- A modulus-10 binary counter counts from 0 to 9 and repeats.
- The terminal count is the maximum count value before the counter resets.
- The binary representation of the terminal count is 1001 (option C).