Context: Mute swans eat plants that grow underwater or in mud. The shape of the 's beak is adapted to filter through mud for food.
The  gathers muddy water in its beak and then pushes it out through gaps along the sides. Bits of food, such as plant roots, are left behind inside the swan's beak.
Figure: mute swan.
Which bird's beak is also adapted to filter through mud?
A. ringed teal
B. northern mockingbird
Identify the correct option from the choices provided and respond with the letter of the correct option.

A