________ how others react to the book you have just read creates an added pleasure.

(2013·浙江，7)

A．Hearing? B．Hear

C．Having heard? D．To be hearing

(2013·高考浙江卷)________ how others react to the book you have just read creates an added pleasure.

A．Hearing? B．Hear

C．Having heard??? D．To be hearing