The progressive era brought significant reforms to American industrial capitalism and to the American political system, through participation and activism by ordinary Americans. The progressives had organized to improve the working and living conditions for poor people, only really to address the glaring social and environmental problems, as well as expand opportunies for democratic involvement in the political system.
<u>"confirming that it is not an online source" </u>is wrong. The problem is not the fact the source is online, but if it's credible.
<u>"determining whether or not it is well-known" </u>well-known sources might still be wrong. Being known does not make something true.
<u>"d. determining whether it is a secondary source" </u>again, it has nothing at all to do with the validity of the source.
So the answer is:
b. checking its conclusions against other sources
The best way is to check the source and compare to different ones that talk about the same subject. Comparing different conclusions of different authors and seeing different points of view about the same thing is often the best way.
If the link has a .gov or .edu it is always reliable. You can also look for contact information of the writer. If the person is a known pro then it could be reliable. Next you look at when it was posted, old websites tend to not have current true information due to the fact that every day there is something new learned by someone.
Hope this helps you find if the source is credible