Masacre de Nanjing donde las fuerzas imperiales japonesas ejecutaron deliberadamente a civiles chinos. Se estima que entre 50.000 y 300.000 personas murieron durante la masacre.
Answer:
B: Bronze
Explanation:
Because this brought humans into the bronze/copper age. And bronze is a copper and tin alloy
People helped hide fugitive slaves along the Underground Railroad and wouldn't turn them over to slave catchers.
