Final answer:
Roberto, a clinical psychologist in California, likely administers psychotherapy to his patients rather than prescribing medication, unless he has completed additional training for prescription privileges.
Step-by-step explanation:
Given that Roberto is a clinical psychologist residing in California, the most likely true statement about Roberto is that he administers psychotherapy to his patients. Clinical psychologists, including those in California, generally have a PhD or a PsyD and are trained to provide psychotherapy and counseling, administer and interpret psychological tests, but not to prescribe medication. In California, clinical psychologists can obtain prescription privileges, but it requires specific additional training and certification through a psychopharmacology program. However, the majority of clinical psychologists do not have these privileges.