Read the following scenario and answer the question that follows:

Sibusiso is employed as an estate agent at New Horizons Property Group (Pty) Ltd. During a marketing campaign, Sibusiso overhears one of the company directors along with some of his colleagues making derogatory remarks about Sibusiso’s sexual orientation. The next day, Sibusiso finds out that he was denied a promotion which he qualifies for. Sibusiso is very upset and believes that he was denied the promotion based on his sexual orientation. He approaches you for legal advice.

Which specific fundamental right has been infringed in this scenario?