Which of the following best defines an established problem, worsening?

a. When performing physician orders specific laboratory, pathology, or diagnostic tests for the purpose of identifying the differential diagnosis of the undiagnosed new presenting problem
b. A patient's presenting problem that has already been diagnosed by the performing physician and has become worse
c. A patient's presenting problem that has already been diagnosed by the performing physician and has remained stable or shows improvement
d. A patient's presenting problem that has already been diagnosed by the performing physician

b) A patient's presenting problem, which has already been diagnosed by the performing physician and has become worse