Final answer:
Sentence C) lacks proper parallel structure by mixing grammatical forms; the actions listed should be presented with similar construction to maintain parallelism.
Step-by-step explanation:
In analyzing the sentences provided for parallel structure, sentence C) “Martha said that she was so good at singing that she could make hymns soar, rock and roll, and even play some soul music.” does not maintain a proper parallel structure. The sentence lists abilities with different grammatical forms: an implied ability to “make hymns soar” (verb phrase), “rock and roll” (noun), and “play some soul music” (action with an object). For proper parallel structure, the actions should be presented similarly, such as “make hymns soar, make rock and roll vibrate, and make soul music come alive,” or a similar construction that maintains parallelism.