Answer/Explanation:
China's one-child policy was introduced in 1979 and ended in 2015. Evident to the name of the policy, each couple was allowed to have one child only. The government believed that reducing the number of people born would reduce the strain on the country's resources; however, there were many "side effects" that affected China negatively.
In order to reinforce this policy, couples who were expecting more children were forced to have abortions. Some couples had their second child born in secret, but these children would be without a government identity. As a result, the child could not attend school or receive any social assistance and would have trouble finding work later on.
When there is only one child in a family, the child ends up receiving all of the attention from their parents and grandparents. They were more likely to be self-centred, uncooperative and even narcissistic.
That child would grow up and eventually start their family, all while their parents enter old age. Having to care for their own family and both of their elderly parents puts extra stress on one person, as opposed to if they could have shared that responsibility with a sibling.
There were particularly more boys than girls born during the policy because boys are traditionally preferred over girls. Many couples who found out they were having a girl would get an abortion. When boys come of age, this makes it more difficult for them to find a bride since there are fewer girls in society. This results in higher rates of depression and more cases of sexual harassment.