_________ is a mono-alphabetic encryption code wherein each & every letter of plain-text is replaced by another letter in creating the cipher-text.

A) Caesar Cipher

B) Playfair Cipher

C) Monoalphabetic Cipher

D) Polyalphabetic Cipher

Correct Answer : Caesar Cipher

Explanation : Caesar Cipher is the simplest type of substitution cipher with a mono-alphabetic encryption code wherein each letter of plain-text is replaced by another letter in creating the cipher-text.