How can users futher filter a plotted layer in Maps, say for example by Opportunity Stage?

How can users futher filter a plotted layer in Maps, say for example by Opportunity Stage?
A . Create a filtered report, identify it as a Base object from the Report object and then use it as a basis for the Layer
B. First create the Layer by gathering Opps, group them by Stage and once the Layer is generated the user will be able to click certain checkboxes to only plot the markers of the stages desired.

Answer: B