Which of the Following Is True of the Subjects of Bargaining

Which of the following is true of the subjects of bargaining?

A) Failure to bargain over subjects such as rates of pay, wages, and working hours are acceptable labor practices.
B) Issues like the commitment of capital and the basic scope of the enterprise are subjects that parties must mandatorily bargain over.
C) Inclusion of a permissive subject in the bargaining process in one year makes that subject an issue of mandatory bargaining in any future contract.
D) Contract clauses that would require unlawful discrimination by the employer are illegal terms that are excluded from the bargaining process.