One does not "click" "A" in video games, let alone in a Mario video game as the Mario hat in the pic implies the game being played is. "A" is a key on the keyboard or a button on most controllers/gamepads. This button is "pressed", "hit" or "tapped" to activate the function that button is assigned to perform; e.g. making your character in the game jump. The term "Click" is used exclusively with the action of activating a button on the mouse (primarily the left mouse button) after having positioned the cursor over an element of the GUI on the screen, where "clicking" the mouse button interacts with that element.