Answer:
There are four options for this question, and the letter C is correct:
a) glyphs.
b) symbols.
c) control characters.
d) command characters.
Step-by-step explanation:
Control characters is a code with a number a several characters, Procedural signs in Morse code are a form of control character, a form of control was introduced in 1870 called Baudot code: NUL and DEL, and was introduced in 1901 Murray code added the carriage return (CR) and line feed (LF).
For example:
(null, NUL, \0, ^@) used by many programming language like "C".