Answer: First check to see if the shoots are emerging from above or below the graft union. Usually the bark looks a bit different (color, texture pattern, etc.) above and below the union. The trunk may also not be the exact same size above and below the union.
If at least one shoot is emerging above the union, it may be trained into a new tree. Remove all other shoots and carefully cut the trunk off just above the shoot you keep.
If all shoots are emerging from below the graft union, they are rootstock and will not produce a quality fruit. You can still keep one to rebuild the tree, but you will have to graft or but it to a new, desirable variety.
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