The correct option is C All the halogen acids (HF,HCl,HBr and HI) are stored in glass bottles
(A) The glass is opaque due to scattering of light by small crystals therein. However, it absorbs ultra-violet light.
Thus, the option A is correct.
(B) It consists of silicates of sodium and alkali.
The ordinary glass may be represented as Na2O.CaO.6SiO2.
Thus, the option B is correct.
(C) HF causes marking on glass as glass dissolves in HF with the liberation of silicon tetrafluoride gas.
Thus, the option C is correct.
(D) Except, HF all the halogen acids (HCl,HBr and HI) are stored in glass bottles.
Hence, the option D is incorrect.