From the following options, choose the most suitable form of the word…

The correct answer is Option (2) → fell

Complete sentence: Nobody is allowed to fell the trees in the protected areas of Nagarjuna forest. After "allowed to", the base form is needed, and the trees are the object, so the verb is to fell the trees.

Option	Form and use	Example
(1) fall	Fall (fall, fell, fallen) is intransitive: a tree falls by itself, but nobody can "fall a tree". Fall means to drop down by itself and takes no object, so "to fall the trees" is wrong.	The old tree may fall in the storm.
(2) fell (answer)	Fell (fell, felled, felled) is a transitive verb meaning to cut down a tree. It takes an object.	The workers had to fell the dead tree before it crashed onto the road.
(3) fallen	Fallen is the past participle of fall. It cannot follow "to" here.	Several branches had fallen overnight.
(4) have fall	"Have" needs a past participle (have fallen), so "have fall" is ungrammatical. It would also give the wrong verb.	The leaves have fallen from the trees.

Contrast: fell (cut down) takes an object: workers fell a tree. Fall takes none: a tree falls.