Under what circumstances can a very small treatment effect be statistically significant? a. With a large sample and a large standard deviation b. With a large sample and a small standard deviation c....

Under what circumstances can a very small treatment effect be statistically significant?
a. With a large sample and a large standard deviation
b. With a large sample and a small standard deviation
c. With a small sample and a large standard deviation
d. With a small sample and a small standard deviation