Select the olfactory indicator from among the given options.
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. Clove oil.
Clove oil is an example of an olfactory indicator. It is known to change its smell when exposed to acidic or basic conditions. In an acidic environment, clove oil emits a distinct aroma, while in a basic environment, the smell alters or may disappear. Olfactory indicators like clove oil are used in various experiments to detect the pH of a solution based on the change in odour, offering a simple way to test for acidity or alkalinity.