Which item is considered illegal to inquire about during a job application process?

Inquiring about a candidate's date of birth during the job application process is considered illegal because it can lead to age discrimination. Federal laws, including the Age Discrimination in Employment Act (ADEA), protect individuals 40 years of age and older from discrimination based on age in various employment practices. Questions related to age, and by extension date of birth, may inadvertently reveal a candidate’s age and could bias hiring decisions, affecting fairness in the hiring process.

On the other hand, asking about work experience, education, and professional references is legal and standard practice in job applications. These areas focus on the candidate’s qualifications and abilities relevant to the job and do not inherently introduce risks of discrimination based on protected characteristics like age.