Question

Which of the following can fly backward?
(a) Penguin
(b) Albatross
(c) Hummingbird
(d) Elephant bird

Answer 1

Generally, the shapes of their wings are long, narrow, and tapered, which are responsible for moving more quickly and easily through the air. It is like a miniature helicopter. Like a helicopter, flying birds can drift, it can fly right to left, left to right, diagonally, forward, and even in reverse.

Complete answer:
In comparison to other birds, the design of the wings of a hummingbird is totally different. The hummingbirds have a unique ball and socket joint at the shoulder that allows the bird to rotate its wings $180^o$ in all of the directions. Moreover, the shoulder and elbow joints of the wing are near their small bodies, permitting the wings to tilt and turn. These qualities permit hummingbirds to change direction bearings in a manner different birds can't.

Additional Information:
The hummingbird can turn its wings around and around making a circle which forms the figure eight. So not only does the hummingbird fly backward, it does so with great speed and grace. Indeed, they fly at a speed of up to 30 mph. The hummingbird has a heart rate that is around 1,200 beats per minute or more. The fast-paced wing-flapping creates a humming noise, which gives them their name.1/3rd of hummingbirds total weight comes from the muscles it uses to fly. Hummingbirds are continually eating so as to fuel their flight dexterity; they have the highest rate of metabolisms of all birds.
So, the correct answer is ‘Hummingbird’.

Note: Flycatchers, warblers, egrets, & herons have the ability to move backward for a brief spell when in the air by using the wind currents to hold them up and moving them to seem that they're flying backward. Generally, they do not really have the ability to propel themselves (fly) backward because according to world atlas & other sources, their wing structure is not made for that movement and their muscles are not strong enough. They need to fly in the wind to move backward, they can do so by the support of the wind.