Look at the picture and choose the correct option that should be in capital letter.

Tony is my best friend.

The correct answer is: Tony

Tony is a name of the person and so, it denotes a noun. Noun should be capitalized always whenever it comes in a sentence at any place. Hence, Tony is capitalized. No other words are need to be in capital because, other words are just ordinary words and do not mention any noun form. Those words are adjective and collective form of noun. Sometimes, friend is also capitalized but it will depend according to the sentence.