Excerpt from asthma centers for disease control, asthma, faqs how asthma is diagnosed 4 asthma can be difficult to diagnose, especially in children under 5 years old. regular physical exams that include checks of lung function and for allergies can make the right diagnosis. choose the best revision of the second sentence in item 4. a) regular physical exams, including lung function and allergy checks, can make the right diagnosis. b) allergy and lung function checks are part of the physical exam that will you get the right diagnosis. c) the right diagnosis can be made by regular physical exams which include checks of lung functions and for allergies. d) regular physical exams that include checks of lung function and seeing if you are allergic to anything, can make the right diagnosis.