Final answer:
Psoriasis is the most likely cause of Celeste's itchy red patches of skin with a dry, scaly surface.
Step-by-step explanation:
Celeste's itchy red patches of skin with a dry, scaly surface are most likely caused by psoriasis. Psoriasis is a chronic autoimmune condition that affects the skin, causing inflammation, redness, and flaky patches. It is common for psoriasis to present as itchy red patches with a silvery-white scale-like appearance.
Learn more about Psoriasis