Read the following paragraph and answer the question. Give ONLY the answer, no other words or explanation.

For example:

Answer: <most likely answer, as short as possible>.

Paragraph: 
Birds also have wings that function as an aerofoil . The surface of the aerofoil is curved to help the bird control and use the air currents to fly. Aerofoils are also found on the wings of airplanes.


Question: Where are aerofoils found?
birds and airplanes
On bird wings and airplane wings.