The Metals in Porcelain Bonding Alloys Are Selected and Blended

The metals in porcelain bonding alloys are selected and blended so they have which of the following properties?

A) They have the ability to withstand the low temperatures at which porcelain is fired without distorting or melting.
B) They have a higher thermal expansion than gold alloys used for all-metal crowns.
C) Small amounts of metals such as indium, iron, tin, or gallium are added to form oxides on the metal surface to which the porcelain will bond.
D) Titanium and titanium alloys are added for easy handling.