Which of the following would be likely to be on a firm's letterhead?

A) Firm name
B) Address
C) Phone number
D) All of these choices are correct.

Firm's Letterhead

The official stationary of a company or organization that contains its name, address, logo, and sometimes its directors, used for formal correspondence.

Phone Number

A sequence of digits assigned to a telephone line for the purposes of making and receiving calls.