Juan has been diagnosed as having a substance use disorder. He is addicted to alcohol. His therapist explains to Juan that the disorder severity is considered mild. Based on the criteria for rating levels of severity of substance use disorders, Juan would have symptoms.

Two or three

Explanation:

If a person is suffering from substance use disorder,then he/she might be taking any medication or drug without any control which results in issue of brain functioning and behavior conduction. Substance than can be used in this case are nicotine, alcohol etc.

If a person is diagnosed of having mild substance use disorder then, he/she has two or three elements that match the symptoms or criteria of disease.

According to the question,Juan is at the mild stage of substance use disorder and thus , would be persisting two or three criteria matching the disease symptoms.