Unless the invitation for bids so provides, a bid is not rendered nonresponsive by the fact that the bidder specifies that award will be accepted only on all, or a specified group, of the items included in the invitation for bids. However, bidders shall not be permitted to withdraw or modify "all or none" qualifications after bid opening since such qualification is substantive and affects the rights of the other bidders.
S.C. Code Regs. § 19-445.2075