The underlined pronoun <em>who </em>is used as a D) subject in this sentence. The subject is the doer of the action, the one who left mittens on the ground, in this case.
C.a natural area hope you like my answer
ANSWER:
C. The picture frame, which we bought at a flea market, fell apart when we tried to hang it.
Hey there!
Free verse<span> is an open form of poetry. It doesn't use consistent </span>meter<span> patterns, </span>rhyme<span>, or any other musical pattern. Therefore, It tends to follow the rhythm of natural speech.
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(This is from Wikipedia)