Which one of the following is not due to total internal reflection?

Options

(a) working of optical fibre
(b) Difference between apparent and real depth of pond
(c) Mirage on hot summer days
(d) Brilliance of diamond

Correct Answer:

Difference between apparent and real depth of pond

Explanation:

Difference between apparent and real depth of a pond is due to the refraction of light, not due to the total internal reflection. Other three phenomena are due to the total internal reflection.