Select the most appropriate option to fill in blank number 3.
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. on.
The preposition on is used to indicate a position where something is attached to or supported by a surface.
The phrase "grown on trees" is a way to describe things that are produced or grow while attached to the tree; for example, apples grow on trees.
Hence, option 1 i.e. on is the correct option.