The coach of a national football team found that the best cooperation characteristics of players U, V, W, X, Ｙ, and Z during training are: (1) V and X cannot be on the field at the same time, and neither can be on the field. (2) ) V is not on the field only if U is not on the field. (3) If W is on the field, then X is on the field. (4) If Ｙ and Ｚ are on the field, then W must be on the field. So, if U and Ｚ are both on the court, in order to maintain the best cooperation between players, which of the following can be inferred to be true? ? ['X is on the field and Y is not on the field.', 'V is on the court and he is not on the court.', 'V and W are on the field.', 'Neither D. V nor Hyun are on the court.']