In Boys with Duchenne Muscular Dystrophy, Muscle Weakness Appears First

In boys with Duchenne muscular dystrophy, muscle weakness appears first in the

A) cardiac and respiratory muscles.
B) ankle plantar flexors, facial muscles, muscles involved in speech, and sphincters.
C) neck flexors, abdominal muscles, hip extensors and abductors, and knee extensors.
D) finger flexors and extensors, wrist and elbow flexors.