Question

Although the paramedic had vast experience, he was unable to _____ the problem. 1. diagnosis 2. diagnoses 3. diagnostic 4. diagnose

Answer 1

4) Diagnose

Diagnosis and diagnoses are both nouns, where diagnoses is the plural of diagnosis. Diagnostic can be used as an adjective or a noun. For this question, you are looking for a verb because the paramedic was unable to perform an action on the problem.