If you thought Option A used GDI rendering via TextRenderer.DrawString then give yourself a pat on the back. Your were right and it seems from the comments section that most people also prefer this approach.
Option B was using GDI+ and is the current Krypton 2.8.5 implementation for all text drawing. As a visual difference most people would not notice that Krypton is drawing slightly different from Office 2007 applications which use the Option A approach. But some people have sharp eyes and pointed this out as needing to be fixed. This update will be applied in the next release.
Here is a magnified image of Option A on top …

There is a good reason why I didn’t use the Option A right from the outset. GDI drawing can only draw horizontal text in a single color, but Krypton allows you to draw text in a vertical or even upside down orientation. Krypton also allows you to draw using an image or a gradient between two colors.
So when Krypton detects that you are using horizontal text with a single color it uses GDI and in all other scenarios uses the existing GDI+ method. In practice almost all text is drawn horizontal in a single color so you are unlikely to notice inconsistencies.