A Patient Who Is Human Immunodeficiency Virus (HIV)-Infected Has a CD₄

A patient who is human immunodeficiency virus (HIV) -infected has a CD₄+ cell count of 400/µL. Which factor is most important for the nurse to determine before the initiation of antiretroviral therapy (ART) for this patient?

A) CD₄+ cell count trajectory
B) HIV genotype and phenotype
C) Patient's tolerance for potential medication side effects
D) Patient's ability to follow a complex medication regimen