Of the historical famines, all of the following were governmental policies which contributed to the severity of a country's famine except:
a. Investment in research and development to enhance local agricultural production
b. Laissez-faire (hands-off) trade policy, in which the government refused to change their usual grain export practices despite shortage of food at home
c. Collectivizing all farms and seizing all grain produced, to be redistributed by the government directly
d. Forcibly and instantly re-training farmers with generations of experience into producing new, unfamiliar crops and farming methods