Public key encryption is ________.

• A. Complex
• B. Slow
• C. Expensive
• D. All of the above

Answer: (D)

Public-key cryptography uses asymmetric algorithms that rely on complex mathematics with very large numbers. That complexity makes the operations for key generation, encryption, and verification heavier than those of symmetric ciphers, so they’re slower for the same amount of data. The heavier computation and often larger key sizes also mean more CPU time, memory, and energy are required, which is why it’s considered more resource-intensive or “expensive.” In practice, we use public-key methods to securely exchange a session key and then switch to a fast symmetric cipher to encrypt the actual data, balancing security with performance.