# Which of the following hangs upside down on a tree:-

$\begin{array}{1 1} a)Parrot \\ b)Eagle \\ c)Bat \\ d)Sparrow \end{array}$

Bat hangs upside down on a tree.Bats roost, or perch, upside-down for several reasons. Unlike birds, bats cannot launch their bodies into the air from the ground, because their wings don't produce enough lift to take off like a helicopter.
A running start would help, but bats' hind legs are too tiny to gain enough speed for lift-off.This leaves bats with no choice but to use their claws to climb to a high spot, let go and fall into flight. If sleeping bats need to escape quickly, hanging upside-down means they are already in the perfect position to spread their wings and fly away.