13. A graduate student found four reagent vials (I, II, III, IV) with unclear labels. A lab manager mentioned that one of the reagents could be chlorine-substituted alkane (R-Cl). The graduate student quickly made a judgment after collecting the mass spectra of these four samples. Based on the data, please tell us which vial contains a chloroalkane compound. (A)reagent vial I(B) reagent vial Il (C)reagent vial III (D)reagent vial IV(E)None of them is a chlorine-substituted compound.