A byte consists of how many bits:

A byte is a fundamental unit of digital information in computing and telecommunications. It is universally defined as consisting of 8 bits. This standard allows a single byte to represent 28, or 256, distinct values, which is crucial for encoding characters, small integers, and other data. For example, the ASCII character set uses one byte per character.

• Option A (4 bits) describes a 'nibble', which is half a byte.
• Option C (16 bits) is equivalent to two bytes, often referred to as a 'word' in some older computer architectures.
• Option D (32 bits) is four bytes, commonly known as a 'double word' or a typical word size for many modern processors.