Computer Science for IGCSE & O level - Data Transmission (Section 10 - No. 47)
What is the role of a 'key' in the process of encryption?
To verify the identity of the sender.
To transform the plaintext into ciphertext.
To compress the data for faster transmission.
To create a digital signature.
Explication
The key is used as input to the encryption algorithm, transforming plaintext into ciphertext.