One strould use porcelain and tol metal ...

One strould use porcelain and tol metal containers in a truicrowave oven because...
A. Charge may accumulate on the metal surface and there is danger of getting a shock
B. Porcelain vessels are better conductors of heat and thus food gets cooked quickly.
C. Melal containers might undergo chemical reaction leading to spoilage of food.
D. Porcelain vessels are cheaper than the metal containers.

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