Salma and Maria Are Employees at Welfare Co

Salma and Maria are employees at Welfare Co.Salma argues that substance abuse may not be legal grounds for firing an employee,whereas Maria says that substance abuse is always a legal ground for firing employees.Which of the following is a true statement that best supports Salma's argument?

A) It is illegal for any company to conduct random drug testing of employees.
B) Employees who use drugs are far more productive than their co-workers who stay sober.
C) The Americans with Disabilities Act (ADA) prohibits discrimination on the basis of physical or mental disability only.
D) The Americans with Disabilities Act (ADA) treats substance abuse arising from an addiction as a disability.