Violation
Cephalosporins 1. may be cross-allergenic with penicillin. 2. have a narrower spectrum than penicillin. 3. have a mechanism of action similar to that of penicillin. 4. may cause cholestatic hepatitis.
(1) and (3)
(1) (2) (3)
(2) and (4)
(4) only
All of the above.