The correct answer is option A: workplace discrimination.
The expression "glass ceiling" makes reference to an invisible but true barrier that prevents women and minorities from being promoted to managerial and executive level positions within an organization. Such barriers exist due to implicit prejudice on the basis of sex, age, ethnicity, social status, political or religious affiliation.
The phrase "glass ceiling" is used to describe the difficulties faced by women when trying to move to higher roles in a male-dominated hierarchy. The barriers are most often unwritten, meaning that women are more likely to be restricted from advancing through accepted norms, rather than defined corporate policies.