How were Punjab and Bengal divided to accommodate religious majorities?

Based on the religious majority at the district level

The correct answer is Option 4 -Based on the religious majority at the district level

The two of the Muslim majority provinces of British India, Punjab and Bengal, had very large areas where the non-Muslims were in majority. Eventually it was decided that these two provinces would be bifurcated according to the religious majority at the district or even lower level.

Difficulties associated with the Religious basis of Partition:

To begin with, Muslim-majority areas in British India were not confined to a single belt. They were divided into two distinct regions, one in the west and another in the east.
Furthermore, it is important to note that not all Muslim-majority regions expressed a desire to be a part of Pakistan.
Another challenge arose from the fact that the two provinces with a significant Muslim population, Punjab and Bengal, also had substantial areas where non-Muslims formed the majority. Consequently, it was decided to divide these provinces along religious lines at the district level or even lower.
Additionally, there were major concerns regarding the minority communities residing on both sides of the newly drawn border. Large numbers of Hindus and Sikhs in the regions now part of Pakistan, and an equally sizable population of Muslims in Indian Punjab, Bengal, and to some extent Delhi and its surrounding areas found themselves trapped and displaced.