Option 1:
Scrum Guide first

Scrum Guide is http://www.scrum.org/scrumguides/

Opinion by Ron Jeffries:
The Scrum Guide is not the primary source for Scrum. It is a
hacked-together, poorly edited set of notes about Scrum, much of it
apparently tossed off without regard to other parts.

Worse yet, the Scrum guide has little or nothing to say about the
things that happen to people who try to live by Scrum, or who, worse
yet, would try to guide their projects based on only those 20ish
pages.

The CSM course, which I believe you have taken, takes two or more
days and covers far more than what is in the Scrum Guide. It is
generally understood that the course barely qualifies someone to
begin learning what Scrum is really about. It strikes me as nearly
ludicrous to imagine that following the shortest known document on
Scrum is really the ideal way to go.