The coefficient of apparent expansion of mercury in a glass vessel is `153xx10^(-6)//^(@)C` and in a steel vessel is `114xx10^(-6)//^(@)C`. If `alpha` for steel is `12xx10^(-6)//^(@)C`, then that of glass is
A. `9xx10^(-6)//^(@)C`
B. `6xx10^(-6)//^(@)C`
C. `36xx10^(-6)//^(@)C`
D. `27xx10^(-6)//^(@)C`