Which one is not a vestigial organ?

The forelimbs of a cat and a lizard are used for walking. The forelimb of a whale is used for swimming,and the forelimb of a bat is used for flying. These are examples of:

Give differences between homologous structures and analogous structures.

Which of the following organs is vestigial in humans?

Which one illustrates palaeontological evidence in favour of organic evolution?

Choose the correct statements with reference to organic evolution.
$I.$ Flippers of whale and wings of bat exhibit analogy.
$II.$ Wings of butterfly and wings of bird exhibit homology.
$III.$ Organs with dissimilar structure are called analogous organs.
$IV.$ Organs with similar structure and origin are called homologous organs.