text: The sweat chloride test is the gold standard test for the diagnosis of<unk>  fibrosis. A sweat chloride value of more than 59 mmol/L is<unk>  for<unk>  fibrosis, 30-59 mmol/L needs more evaluation with CFTR genetic analysis and less than 30 indicates that<unk>  fibrosis is unlikely.
option_0: Cystic fibrosis diagnostic study of choice
option_1: Cystic fibrosis other diagnostic studies
option_2: Primary ciliary dyskinesia diagnostic study of choice
option_3: Cystic fibrosis echocardiography or ultrasound
option_4: Cystic fibrosis differential diagnosis
option_5: Respiratory failure diagnostic study of choice
option_6: Cyanosis diagnostic study of choice
option_7: Methemoglobinemia diagnostic study of choice