Question

Which of the following is made possible by the use of Polybius square?

(a) To represent the plain text by smaller set of symbols

(b) To represent the plain text by larger set of symbols

(c) To represent the plain text by the letters of some other language

(d) To represent the plain text by the same set of symbols

The question was posed to me in a job interview.

My question is based upon Cryptography topic in portion Cryptography of Data Structures & Algorithms II

Answer 1

The correct answer is (a) To represent the plain text by smaller set of symbols

Explanation: Polybius square is similar to substitution cipher. Polybius square allows us to cipher the plain text in such a way that a minimum number of symbols are used in the encrypted text.