B.
We have blackout drapes from Bed Bath and Beyond and they do pretty well. The drapes have magnets down the sides so the two or more pieces can be securely connected. We got a double curtain rod so you can't even see them behind my daughter's cute, girly curtains:)
If you are going to order window coverings from online or a shop at home place, I would recommend Budget Blinds (have more than just blinds). They are individually owned so you're dealing with someone that really cares about their end product.