Methicillin resistant staphylococci do not respond to ß-lactam antibiotics because (a) They produce a ß-lactamase which destroys methicillin and related drugs (b) They elaborate an amidase which destroys methicillin and related drugs (c) They have acquired a penicillin binding protein which has low affinity for ß-lactam antibiotics (d) They are less permeable to ß-lactam antibiotics