Josiah Child's “Brief Observations Concerning Trade and Interest of Money” primarily focused on economic policies and trade practices rather than educational reform. Therefore, none of the provided options directly align with his main arguments in this work. However, if you are specifically looking for a notable aspect from Child's broader discussions, he was known to support the idea of education improvements, potentially for both genders in a more general context.
If you had to choose from the options given, the closest would be the education of both men and women, as it generally aligns with progressive views on education; however, it's important to note that this was not a central focus of Child's "Brief Observations."