Answer:
A) child labor laws
Step-by-step explanation:
According to the testimony by John Wright in the "Sadler Report", he talks about how children were forced to do manual labor and the inhumane and unhealthy conditions they were forced to work in. He also noted that some children had to be carried to the factories because they could not walk due to their confinement and poor living conditions.
Therefore, the type of reforms this testimony led to in industrialized nations in the mid 19th century was child labor laws.