Final answer:
Social institutions are the patterns through which a society fulfills its fundamental needs, including religious practices and beliefs, making religion a major social institution and a cultural universal.
Step-by-step explanation:
Social institutions refer to the typical ways society meets its essential needs, including the need for religious beliefs and practices. Religion is a significant social institution comprised of an organized set of beliefs, behaviors, and norms that not only address spiritual concerns but also fulfill basic social needs and values. As a cultural universal, religion can be seen in every society, providing common elements that allow for sociological studies while differing enough from culture to culture to be adaptive to local customs and societal structures.