What was Alfred Stieglitz's role in Modernism in America?

Here are some of the options that represent how important Alfred Stieglitz was for Modernism in America:

1. he aided in the development of Modernism - if it weren't for him, who knows whether Modernism would have ever reached America

2. he was an advocate for photography as art - before him, photography wasn't really given much prominence in artistic circles, however, he was the one to change that