Answer:
A). The belief that society valued boys more than girls.
Step-by-step explanation:
Elizabeth Cady Stanton is a leading American Activist and feminist who fought for the rights of women during the early nineteenth century. She was a prominent figure in the suffrage movement and advocated a change in the lives of the women, in both public and private domains. She asked for equal property rights for women along with equal education, opportunities for employment, child custody issues, and much more. She established three different branches of feminism to overturn gender discrimination and injustices done to women.
As per the question, the childhood belief that inspired Stanton to do so would be 'her belief that society valued boys more than girls' and women have been subject to hierarchical oppression and discrimination. This inspired her to be a feminist and activist to fight for the rights of women and become a leading figure in women's suffrage movement. Hence, option A is the correct answer.