Codes consisting of light and dark marks which may be optically read is known as

Mnemonics
Bar code
Decoder
All of the above E. None of the above

The correct answer is B. Bar code.

A bar code is a series of parallel lines of varying widths and spacing that are used to represent data. Bar codes can be read by optical scanners and are used to identify products, track inventory, and control access to restricted areas.

Mnemonics are memory aids that help people remember information. Mnemonics can take many forms, such as acronyms, rhymes, and images.

A decoder is a device that converts one form of data into another. Decoders are used in a variety of applications, such as telecommunications, data storage, and security.

E is not the correct answer because bar codes are not decoders.