But how does it matter if it's main function of the inhibitors or not?
As antibodies are going to deactivate them anyway and the premise clearly points out that inhibitors are the reason why regeneration is affected.
I can't understand why it's A. Anyways, what's the source?
The 2nd sentence states that: "The reason, recently discovered, is the presence
of nerve-growth inhibitors in the spinal cord". It doesn't say nerve-growth inhibitors are main/only factors that inhibit the damaged nerve's regeneration. "Presence" probably means there are more than one factors could stop the regeneration. Antibodies deactivate just those inhibitors, not others. So we cannot simply conclude these antibodies help to repair damaged-nerves. Hope it helps.
Please +1 KUDO if my post helps. Thank you.
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