Which of the following can be classified under advantages and disadvantages of OFB mode?

[answerhappygod]

i) Transmission errors
ii) A bit error in a ciphertext segment
iii) Cannot recover from lost ciphertext segments
iv) Ciphertext or segment loss
a) Advantages: None; Disadvantages: All
b) Advantages: All; Disadvantages: None
c) Advantages: i); Disadvantages: ii) iii) iv)
d) Advantages: i); ii) Disadvantages: iii) iv)