You are developing a client/server-based application in which the client shall communicate with the server through a trusted channel supported by symmetric encryption. Secret keys shall be generated and changed periodically to secure communication. Which of the following is the best design to generate secret keys in terms of scalability and the work factor? (Source: Wentz QOTD)
A. The client using a pseudorandom number generator (PRNG)
B. The client employing the onboard crypto processor
C. The server invoking the operating system’s API
D. The server utilizing the hardware security module

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You are developing a client/server-based application in which the client shall communicate with the server through a trusted channel supported by symmetric encryption. Which of the following is least likely employed to exchange or distribute the predefined secret key? (Source: Wentz QOTD)
A. Human brain
B. Diffie-Hellman
C. Public Key Encryption
D. USB flash drive dongle

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You are developing a client/server-based application in which the client shall communicate with the server through a trusted channel. Which of the following is the best design of key exchange to encrypt data in transit? (Source: Wentz QOTD)
A. The client encrypts the preshared key using its private key
B. The client encrypts the premaster key using the server’s private key
C. The client encrypts the session key using the server’s public key
D. The client encrypts the master key using the server’s public key

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You are taking the cryptography course and working on the homework to develop a cipher. Which of the following is the best technique to complicate the ciphertext if any alternation of bits in plaintext occurs? (Source: Wentz QOTD)
A. XOR
B. ROT-3
C. Table lookup
D. Rotation of bits

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Alice works for a company where the public key infrastructure is implemented. She sent an encrypted message to Bob. Which of the following is the most likely reason why she employed the AES secret key to encrypt the message instead of her RSA public key? (Source: Wentz QOTD)
A. The performance of AES is faster if the work factor is the same
B. The requirement for AES key length is shorter if the work factor is the same
C. The encryption by the AES secret key is more effective if key exchange is secured
D. The computational complexity for breaking AES is higher if the key length is the same

Kindly be reminded that the suggested answer is for your reference only. It doesn’t matter whether you have the right or wrong answer. What really matters is your reasoning process and justifications.