Under South Carolina law, a person may gratuitously undertake a legal duty to another person even if the law would not have otherwise imposed such a duty. Which of the following is definitialy NOT an example of a gratuitous undertaking: a. Giving direction to a stranger who is lost while hiking. b. A pedestian providing medical assistance at the scene of an auto collision. c. An adult serving as a chaperone on a school trip. d. Volunteering to drive your grandmother to the store