Tooth fillings are often made of gold or porcelain because these materials are
a. explosive
b. nonreactive
c. visually pleasing
d. chemically similar to teeth

Tooth fillings are often made of gold or porcelain because these materials are;

b. nonreactive

That means that they don't corrode or rust and they are resistible to staining.Their  thermal conductibility is low.

Explanation:

Porcelain-fused-to-metal crowns. PFM crowns are an approximately esthetic improvement that has been in use for more than 40 years. In one way, they blend the best of both worlds, a crown made of “refined or noble” metal (gold or platinum), which is strong, fits correctly and is bonded/bonded to the tooth.

i need mutiple choices

answer///carbon;