【单选题】

Three weeks after the application of the spica cast following surgery for an infant, the mother told the nurse that the infant's toes are swollen and cool to the touch. Which of the following would the nurses suspect
A．Cotton wadding lining of the cast has shrunk.

B．An infection has developed under the cast.
C．Child's feet were in a dependent position.
D．Child has outgrown the spica cast.