China tried that in an effort to limit the population of China. The problem was that people were not content to have just 1 child. There was too much tradition about family life and gender of the children. That policy "one child per couple" has since been revoked in 2016 after 4 decades of enforcement.
Like the Chinese government, it is a fine statement in theory but not a good one one when you have to implement it into policy without more consideration of the other facts.
So I don't agree with the statement without more facts (like the % of an aging population)
Only 1- the experiment can not show a cause and effect relationship if there are more than one factors contributing to the outcome.
Answer:
B. The distribution of traits in a population
When a single cell organism splits in too
