What feature of the Stanley Quencher H₂.0 FlowState stainless steel vacuum-insulated tumbler is designed to keep beverages at the desired temperature?
A) Insulated design with a thermal conductivity of k₂
B) Vacuum insulation with a heat transfer coefficient of h₂
C) FlowState lid with adjustable temperature control
D) Dual-wall construction with an inner layer of reflective materia