【題組】What is available at no cost to participants during the grand opening event?
(A) Free parking for up to 2 hours and a complimentary snack bar during the grand opening event.
(B) Free monthly membership for one month for those who sign up on the day of the grand opening event.
(C) Free trial session with expert coaches who will provide personalized advice and demonstrate proper techniques for indoor rock climbing.
(D) Free climbing gear rental including harnesses, shoes, and chalk bags for the duration of the trial session at the grand opening event.