Many of them chiselled from solid rock centuries ago the mountainous regions are dotted with hundred...........

General Knowledge (CLAT) Sentence Improvement

Direction: In each of the following sentences, some part of the sentence or the entire sentence is underlined. Beneath each sentence, you will find four ways of phrasing the underlined part. Choose the most appropriate option given in each of the sentences given below that is the best version than the underlined part of the sentence.

Many of them chiselled from solid rock centuries ago the mountainous regions are dotted with hundreds of monasteries:

The mountainous regions are dotted with hundreds of monasteries, many of which are chiselled from solid rock centuries ago.

The mountainous regions are dotted with hundreds of monasteries, many of them chiselled from solid rock centuries ago.

Hundreds of monasteries, many of them chiselled from solid rock centuries ago, are dotting the mountainous regions.

Chiselled from solid rock centuries ago, the mountainous regions are dotted with many hundreds of monasteries.

Explanation:

The mountainous regions are dotted with hundreds of monasteries, many of them chiselled from solid rock centuries ago.
The monasteries are described as being chiseled out from solid rock and their presence has dotted the mountainous region!
Option '2' is the only option which captures the above extract is a proper way with using no other words than those mentioned in the question.