Which of the following restrictions on commercial speech were held to be constitutional by the ...

Which of the following restrictions on commercial speech were held to be constitutional by the Supreme Court?
 a. a Virginia law prohibiting advertising in Virginia papers about abortion services in other states when abortion was illegal in Virginia
  b. a Virginia law prohibiting the advertising of prices of prescription drugs
  c. a Kentucky restriction prohibiting lawyers from sending letters to prospective clients, known to face legal problems, soliciting their business
  d. all of the other choices were constitutional
  e. none of the other choices were constitutional