IMSO 2018 Science International - Theory I Question 3

Which of the following electrical appliances will produce heat when they are
turned on?
(1) air-conditioner
(2) electric bulb
(3) fan
(4) refrigerator
A. (1) and (2) only
B. (1) and (3) only
C. (2) and (3) only
D. (1) (2) (3) and (4)