Question

Which sentence contains an adjective clause? A. Jan saw a stranger's wallet lying on the ground. B. The man whose wallet Jan found gave her a reward. C. Last Tuesday morning, Jan fed the ducks in Paradise Park. D. The park on the east side of town is a good place to walk and bike.

Answer 1

I will also agree that B: The man whose wallet Jan found gave her a reward.

Characteristics of Adjective clause:

First, the sentence must have a verb and a subject.

Second, it must have a relative pronoun (i.e. that, which, whose, whom, and who) or relative adverb (why, where, and when).  If you notice, the relative pronouns in a round about way refers to someone or something. For example, who does the wallet refer to? It refers to the man. The relative adverbs as you can tell answer question words. 

Pattern to look for:

Sometimes it is tricky to find clauses.

With Relative Adjectives there are a couple of things to look for.

The beginning should start with a relative pronoun or relative adverb then add a subject and finally add a verb: RP (or RA) + S+ V= relative adjective clause

Another formula for finding  a relative adjective is Relative pronoun acting as the subject  with a verb added: RP as S + V.

Hopefully this helps and good luck.  

Answer 2

B. An adjective clause must contain a subject and a verb, begin with a relative pronoun, and answer the question what kind? how many? which one?