Answer:
Muckrakers as President Roosevelt denominated them, was the group of people that informed the labour and government injustices of the progressive era to the public.
Step-by-step explanation:
First of all, there has to be a very clear explanation here. Child laborers were informants included in the "laborers informers group" integrated by all kind of worker, but they and women are key here because there were not effective protective laws for them. In second place, once government social workers, lawyers and activists knew about the inhuman conditions and the injustice treatment labourers suffered, they fought against corporations to provide better treat to laborers. Then, in third place businessmen were main players because majority of them took advantage of people and abused from laborers by not providing them a fair contract. However, Muckrakers or as President Roosevelt called them "the man that rak the muck" were the people who reunited the information and made i public, they were social activist from different backgrounds but the most notable were journalists. The important fact here is that they worked with government, laborers and even some businessmen to make public the atrocities of the era.