The answer is d. The hardware has a terrible time translating binary into decimal. Computers in general don't like "talking" to people. D is wrong.
bits are part of bytes.You use bits to make up bytes, not the other way around. Bit's are what computers use to construct their "speech." Bytes make it more convenient to convert from Hex(or binary) to decimal. C is wrong.
A is wrong. There are only two numbers in the binary system -- one and zero. Not three.
B is the correct answer.