Which of these is a proper noun?
A. Doctor
B. Uncle
C. Tim
D. Robot

Tim is someone's name, and thus, is a proper noun.

Explanation: A proper noun is a specific noun. For example, "lake" is a common noun and thus do not need capitalization but Lake Michigan is a specific noun (because it's a specific place) and does need capitalized. All proper nouns need capitalization, and a common proper noun is someone's name.

Doctor can be used generally, you could say, "I think I need to go see a doctor" so that's not it

Uncle could work if you were referring to someone specifically. "My uncle is coming over" is using it in a general sense, but, "My Uncle John is coming over" is more specific, so that would be a specific noun but in this case, it isn't.

Robot by itself is a common noun so it isn't an option. For example, "did you see this cool robot she's working on?" It's used in a general sense.

A proper noun is a name used for an individual person, place, or organization, spelled with initial capital letters so the answer is Tim.

(Hope this helps) Sky

a lot

explanation: