Question $5$

What properties define a "trustworthy" encryption algorithm?

Based on sound mathematics, analyzed by experts, and withstands the test of time

Large key size, resistant to brute$-$force attacks, and high computational complexity

High encryption speed, compatibility with all operating systems, and ease of implementation

Resistance to statistical analysis, immune to ciphertext$-$only attacks, and low memory usage

Question $6$

What is the purpose of authenticated encryption $($AE$)?$

To prevent undetected modification of ciphertext.

To ensure confidentiality of the plaintext.

To generate a pseudorandom stream of bits.

To choose a prepackaged set of algorithms.