Which One of These Conditions Must Exist If a Rights

Which one of these conditions must exist if a rights offering is to be successful?

A) The rights cannot be resold.
B) The book value per share must be less than the subscription price.
C) Shareholders must be able to obtain one new share for every right they receive.
D) The issuer must guarantee to repurchase the rights at the offer price if the market price declines.
E) The subscription price must be less than the market price.