2. Which of the following statements about drug treatment IS TRUE? A. Residential therapy centers are more effective than methadone maintenance programs.
B. Methadone maintenance is more effective than outpatient drug-free programs.
C. The most effective treatment programs last less than 3 months but more than a week
D. The length of time spent in treatment is the single best predictor of a successful outcome.

D. The length of time spent in treatment is the single best predictor of a successful outcome

Explanation:

The success of a treatment is correlated to the length of the treatment period, which is the time spent in treatment

The longer the episode of treatment the increases in the probability of a successful outcome, than the outcome probability obtained in a short period or length of treatment time.

The quality of the treatment program and the candidate motivation are usually related to the retention rates of candidates in a program.

the gravitational force on an object increase as the mass of an object also, im not going to report you, but this question should be under the science category, not health