Answer:
Adjective clause.
Explanation:
Adjective clauses are those dependent clauses that modify the noun or pronouns in the sentence. They can be easily identified by the presence of the relative pronouns (who, which, whom, whose etc) which begin the dependent clause.
In the sentence -
"Mr. Wendt, who lives next door, is a generous man"
the dependent clause is "who lives next door". Now, the beginning of the dependent clause is "who" which is a relative pronoun for the main noun "Mr. Wendt".
Thus, the type of clause used in the sentence is an adjective clause.
