Which of the Following Is a Characteristic of a Binomial

Which of the following is a characteristic of a binomial problem?

A) There are n identical trials, and all trials are independent
B) Each trial has two possible outcomes which are traditionally labeled "failure" and "success" and the probability of success p is the same on each trial.
C) We are interested in x, the number of successes observed during the n trials.
D) All of these are characteristics of a binomial experiment.
E) None of these