Two vaccines are described in a. and b. below. For each, predict whether the vaccine would activate a cytotoxic T cell response or just a T helper and B cell response. Explain your answers by describing what you have learned about antigen processing and presentation. Be sure to include key steps and molecules involved in each processing pathway. a. A UV- inactivated ("killed") viral preparation that has retained its antigenic properties, but cannot invade or replicate in host cells. b. An attenuated active ("live") viral preparation that has low virulence but can still invade and replicate in host cells.