Which form of kanamycin is typically used? - (Jul/02/2010 )

Kanamycin sulfate comes in three forms: A, B and C. You can buy the mix or even buy them separately. Which is typically used for LB and LB agar? I was guessing the mix but I wanted to be sure before we bought more and made everything up.

Thanks a lot.

I bought my Kanamycin from Merck. It is powder form then I make 100mg/ml stock solution with it.
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