Zoe transfers the business assets or her sole proprietorship to C Corp. in a nontaxable exchange on September 1, 20X1. The holding period for all of Zoe's stock in C Corp. commences on: a. the date of exchange b. the first day of the year I which the exchange took place c. the holding period for the assets in the sole proprietorship d. the last day of the year in which the exchange took place