A psychologist wishes to estimate the level of depression of patients that seek outpatient psychotherapy. She decides to select her sample from ten outpatient clinics that have at least 50 patients in each clinic. She randomly selects six patients from each clinic and administers a test that measures depression on a quantitative scale. Consider the following propositions: Proposition I: If this study is carefully performed twice, we are guaranteed to sample the same subjects. Proposition II: If this study is performed twice, we are guaranteed to observe exactly the same depression scores, as long as there are no mistakes in calculation or data entry.

Proposition I is true and Proposition II is true

Proposition I is true and Proposition II is false

Proposition I is false and Proposition II is true

Proposition I is false and Proposition II is false

None of the above