Seems to me you were not convicted of a felony - correct?
Seems to me that you were not subject to deferred adjudication for a felony if it was converted to a misdemeanor - correct?
So reasonable interpretation of the question (even if slightly confused) would be "No" as they could have clarified the concept of felony conversion to misdemeanor as another add-on to qualify the question in a better manner as to adjudication. You are not a lawyer so cannot be expected to know exactly what they "infer" as to the question taken at face value -- capice??
My answer is not intended to be giving legal advice and this topic can be a complex area where the advice of a licensed attorney in your State should be obtained.