Inflammation- Giant cells origin

A 40-year-old African American female presents to the clinic complaining of cough and fever. Her chest x-ray shows bilateral hilar lymphadenopathy and increased angiotensin-converting enzyme (ACE) levels. The lymph node biopsy shows granulomas with numerous epithelioid cells and a few multinucleated giant cells. These multinucleated cells are derived from which of the following inflammatory cells?