What is the key difference between Electronic Codebook mode and other block cipher modes like...

Plaintext patterns are concealed by XO Ring with previous cipher text block but input to the block cipher is not randomized.

Plaintext patterns are concealed and input to the block cipher is randomized by XO Ring with previous cipher text block.

Plaintext patterns encrypted with the same key will always generate the same

Cipher text pattern

Plaintext patterns are not concealed but input to the block cipher is randomized by XO Ring with previous cipher text block.