The process used in most block ciphers to increase their strength is

The process used in most block ciphers to increase their strength is

A.
Diffusion

B.
Confusion

C.
Step function

D.
SP-network

Explanation:
D: The SP-network is the process described by Claude Shannon used in most block ciphers to increase their strength. SP stands for substitution and permutation (transposition), and most block ciphers do a series of repeated substitutions and permutations to add confusion and diff usion to the encryption process. Page 316.