请选择CBA:K'P1w*h:A'o)I4X4v,a A: What is your father doing? B: He is talking_______an old man.9s,~7I+{,z4m6y6U5V
A. at9s,~7I+{,z4m6y6U5V
B. to9s,~7I+{,z4m6y6U5V
C. in9s,~7I+{,z4m6y6U5V