A well-known computer game keeps records of the number of games played and the number of games played on the computer. It is a shuffle of the cards before every game, which means that the result of the game is different from one round to another and depends on the participant’s ability. Let X be the number of games won in 100 games. In which of the following circumstances is X a binomial random variable?
(A) The same person performed each game with improved skill throughout 100 games.
(B) Five players from five players of different skill levels were permitted to participate in 20 matches in succession.
(C) Players with different skill levels were given the right to compete until they lost three games, leading to the playing of 100 matches.
(D) A pair of players with equal skill levels each were able to play from day to day. One game per day for 50 days, their skills stayed the same. For one day.
(E) The two participants with different skill levels competed; the player was allowed to play until a game ended, the other to continue playing until a game was lost, and so on until 100 times were played.