How does family size affect on birth explain​

Family size might adversely affect the production of child quality within a family. ... Controlling for parental family income, parental age at birth and family level attributes, we find that children from larger families have lower levels of education and that there is in addition a separate negative birth order effect.

Like most previous studies, we find a negative correlation between family size and children's educational attainment. The evidence suggests that family size itself has little impact on the quality of each child but more likely impacts only the marginal children through the effect of birth order.

the answer is either c or d i think its d

true