Objects $A$ And $B$ Are Made of the Same Substance, but Object $A$

Objects $A$ and $B$ are made of the same substance, but object $A$ is twice as massive as object $B$ . Object $A$ originally has a temperature of $100^{\circ} \mathrm{C}$ and $B$ has a temperature of $0^{\circ} \mathrm{C}$ . Suppose these objects are put inside a well-insulated cup and are allowed to come to a common temperature $T_{f}$ . What is that temperature? Select the closest answer.

A) $75^{\circ} \mathrm{C}$
B) $67^{\circ} \mathrm{C}$
C) $50^{\circ} \mathrm{C}$
D) $33^{\circ} \mathrm{C}$
E) $25^{\circ} \mathrm{C}$