Final answer:
The condition most likely present with a non-removable whitish film on the buccal mucosa is candidiasis, indicated by white patches and pseudomembranes, treatable with antifungal medications. Option b) Candidiasis is the correct answer.
Step-by-step explanation:
When observing a translucent-to-whitish irregular film on the buccal mucosa that is non-removable with gauze, candidiasis is the most likely condition present. Candidiasis, or thrush as it is commonly known, is indicated by white patches and pseudomembranes.
These white lesions can be indicative of an overgrowth of the yeast Candida albicans, which is known to occur opportunistic infections often linked to an immune-compromised state, such as in HIV patients.
Candidiasis is treated with a range of antifungal medications, including topical agents like nystatin or clotrimazole oral suspensions and, in more serious cases, systemic azoles like fluconazole or itraconazole, or even amphotericin B for severe or resistant strains of Candida.