Which of the following is false concerning the employer's substantive affirmative defenses? Please referency your answer
a) A citation may be vacated if the employer proves that an alternative method of protection was used.
b) In considering the infeasibility defense courts have concluded that it encompasses both technological and economic factors.
c) The commission has held that employers need not strictly comply with a standard to the extent that compliance would create greater hazards than non-compliance would.
d) The commission requires the employer show two elements of proof that he required his employees to take protective measures to comply with the standard.