Final answer:
The preferred study for the diagnosis of melanoma is biopsy, which involves the removal of a small sample of tissue from the suspicious mole or lesion.
Step-by-step explanation:
The preferred study for the diagnosis of melanoma is biopsy. A biopsy involves the removal of a small sample of tissue from the suspicious mole or lesion. The sample is then examined under a microscope to determine if it is cancerous. Biopsy is the most accurate method for diagnosing melanoma.