Which of the Following Statements Is Correct Concerning Porcelain Veneers

Which of the following statements is correct concerning porcelain veneers?

A) Veneers are usually recommended to improve chewing efficiency of posterior teeth.
B) The color of the finished veneer can be affected by the shade of the underlying tooth structure and by the color of the luting agent.
C) Porcelain veneers do not involve preparation of tooth structure.
D) Provisional coverage is required following impressions for porcelain veneers.