Which type of discrimination does the Age Discrimination in Employment Act specifically guard against?

The Age Discrimination in Employment Act (ADEA) specifically guards against discrimination based on age for individuals who are aged 40 and over. This federal law was enacted to promote the employment of older individuals and to prohibit arbitrary age discrimination in employment. It applies to employers with 20 or more employees and covers various employment practices, including hiring, promotions, wages, and termination. The focus on individuals 40 and older reflects the intent to protect a demographic that may face significant challenges in the job market due to ageism, ensuring they do not face disadvantageous treatment in employment opportunities simply due to their age. The other options represent different forms of discrimination that are addressed by other laws, but they are not within the specific scope of the ADEA.