<span>In randomized controlled trials, people are randomly assigned to each category to offset any potential bias.
</span>Selection bias<span> is the phenomenon where</span><span> the </span>selection<span> of people or groups is not adequately randomized to offset potential bias in research studies. This in turn does not ensure that the study samples included in research are representative of the population needed to be tested on.</span>
Answer: High living standards enables citizens to carry out investments in their nation which directly leads to the future growth of a particular nation.
Explanation: High standard generally refers to wealth, comfort, material goods and necessities of certain classes, it could as mean the economic ability of an individual to buy whatever he wants.
In countries with high standard of living individuals have vast economic strength, so they can easily start up any business they desire. These businesses either large or small are building blocks for effective growth of economies of countries.
Answer:
A.John Brown is the amswer
The number of one-child families continues a steady increase, making up about 20 percent of American families.