Q1. Which one of the following best expresses the central argument of the passage?
A. Pilot programmes provide unreliable evidence and should not be used as the basis for national policy.
B. A programme that succeeds on a small scale should normally be expanded gradually because gradual expansion guarantees similar results.
C. Evidence that an intervention works on a small scale does not by itself establish that it will work at a larger scale, because expansion can alter resources, incentives, prices, institutions and political conditions.
D. The principal obstacle to scaling successful policies is the inability of governments to recruit sufficiently competent administrators.