Final answer:
Villous adenomas are more likely to become malignant compared to tubular adenomas.
Step-by-step explanation:
Tubular and villous adenomas are epithelial benign lesions of the small intestine. Regarding which one is most likely to become malignant, villous adenomas have a higher risk of becoming cancerous compared to tubular adenomas. Villous adenomas have a finger-like appearance and are more likely to have dysplasia, which is a precancerous condition that can progress to cancer over time. On the other hand, tubular adenomas have a lower risk of malignancy.