Which of the Following Describes a Situation That Falls Under

Which of the following describes a situation that falls under an exception to the rule on confidentiality under the Model Rules?

A) An adult child of a parent is charged with theft, and the parent calls the child's attorney and demands to know what the child told the attorney.
B) The wife of a newly married couple calls the husband's attorney and requests information on the husband's business dealings prior to the marriage.
C) A shareholder of a large corporation sends a letter to the corporation's outside counsel demanding information regarding stock options granted to the corporation's president.
D) A law firm represents a seller in a business transaction, and two years later, the buyer serves a subpoena on the law firm as part of lawsuit between the buyer and seller.