a. cbc added bytes to the corrupted byte but the information outside of the corrupted byte remained retrievable
ecb lost all of the information after the corrupted byte
ofb replaced the corrupted byte and all other data remained retrievable
b. ?
c. CBC is not tolerant to dropped or corrupted bytes and in any data transfer scenario CBC would significantly less fault tolerant even if redundant messages are sent. CBC encoding data can be easily recovered especially when multiple copies of encoded information are sent.