Final answer:
The document frequently encountered in Mesopotamia is the cuneiform tablet, used for detailed records and written in a script that evolved over time.
Step-by-step explanation:
The kind of document frequently encountered in the writings recovered in Mesopotamia is b. Cuneiform tablet. Cuneiform writing was mainly inscribed on clay tablets using a stylus to stamp the wet clay. These tablets often included records such as royal inscriptions, contracts, letters, and literature. They provided a detailed view of Mesopotamian social, religious, and economic life. Cuneiform script was developed around 3400 BC and was used to record the Sumerian language and later languages like Akkadian. The evolution of cuneiform from pictographs to a phonetic system allowed the creation of detailed records and literature. Despite the complexity of the cuneiform writing system, scribes utilized it for various records, making it an essential part of Mesopotamian culture.