Final answer:
The Older Workers Benefit Protection Act (OWBPA) amended the Age Discrimination in Employment Act to include employee benefits and provided standards for waivers of the right to sue for age discrimination.
Step-by-step explanation:
The U.S. act that amended the Age Discrimination in Employment Act to include all employee benefits and provided standards for the employee's waiver of the right to sue for age discrimination is the Older Workers Benefit Protection Act (OWBPA), which was passed in 1990.