When cooking tomato sauce, its high acid content requires using A. additional oil. B. starch slurries. C. a pot made of a nonreactive material. D. a wooden spoon.

When cooking tomato sauce, its high acid content requires using a pot made of a nonreactive material.
Tomatoes are very acidic when you use metal cookware it gives more taste bitter and metallic. 
It is recommended to use a non-reactive cookware like stainless steels.