-8 is equal to signed binary number         *(A) 10001000(B )10000000(C) 00001000(D) 11000000

The answer is (B) 10000000.

Here's the step-by-step process:

1. First, we need to understand that binary numbers can be represented in signed magnitude, where the leftmost bit is used to represent the sign of the number (0 for positive, 1 for negative), and the remaining bits represent the magnitude of the number.

2. In this case, we are looking for the binary representation of -8.

3. The binary representation of 8 (ignoring the sign for now) is 1000.

4. Since we are looking for -8, we need to represent this as a negative number in signed magnitude. This means we put a 1 at the front of the binary number to represent the negative sign.

5. However, we need to make sure the binary number has 8 bits (as per the options given). So, we pad the number with zeros at the front, giving us 00001000.

6. Finally, we add the sign bit at the front, giving us 10000000.

So, the signed binary representation of -8 is 10000000, which corresponds to option (B).