Mujhe aap bahut achchhe lagte ho. Explanation: Mujhe = "I like" (literally "to me" but used for expressing liking). Aap = "You" (polite, formal). Bahut = "Very much." Achchhe = "Good" (plural form, used here as a polite way to refer to someone). So, this sentence is polite and appropriate when addressing someone respectfully. The other options: Mujhe tum bahut achchhe lagte ho (informal, used for friends or peers). Mujhe tu bahut achchha lagta hai (informal, much more casual, and used for someone younger or close). Let me know if you need more explanations!