Read the sentence.

Sami especially enjoyed the brownies, which were chewy, chocolatey, and jam-packed with crunchy walnuts.

Which statement best explains how the underlined clause conveys meaning?

It is a noun clause stating what Sami likes about brownies.
It is an adverbial clause telling why Sami liked the brownies.
It is a relative clause describing the qualities of the brownies.
It is an independent clause explaining how brownies are made.