What part of speech is the word "bad"?

Because of her extreme nervousness, Soon Lee performed the sonata bad during her audition for the college orchestra.]]> What is "bad" modifying?

Because of her extreme nervousness, Soon Lee performed the sonata bad during her audition for the college orchestra.]]> What kind of verb is "performed"?

Because of her extreme nervousness, Soon Lee performed the sonata bad during her audition for the college orchestra.]]> Because of her extreme nervousness, Soon Lee performed the sonata badly during her audition for the college orchestra. Type the correct form of the underlined modifier into the box, then submit it and say the sentence.

Because of her extreme nervousness, Soon Lee performed the sonata bad during her audition for the college orchestra.]]>