Acryptographic attack in which portions of the ciphertext are selected for
trial decryption while having access to the corresponding decrypted
plaintext is known as what type of attack?

A.
Chosen ciphertext

B.
Adaptive chosen plaintext

C.
Known plaintext

D.
Chosen plaintext

Explanation:
The correct answer is “Chosen ciphertext.
In answer Known plaintext, the attacker has a copy of the
plaintext corresponding to the ciphertext.
Answer Chosen plaintext describes the situation where selected plaintext is encrypted and the
output ciphertext is obtained. The adaptive chosen plaintext attack, answer “Adaptive chosen
plaintext, is a form of chosen plaintext attack where the selection of the plaintext is altered
according to previous results.