Correct Option: C

Vancomycin is the antibiotic resistance marker that cannot be used in a cloning vector in gram negative bacteria. Vancomycin acts by inhibiting proper cell wall synthesis in Gram-positive bacteria. Vancomycin treats only gram positive infections (commonly a skin infection, an example of a Gram positive infection). It has little/no use against a gram negative bacteria because vancomycin acts by binding to parts of the cell wall that are present in a gram positive bacteria but not in a gram negative bacteria.