Refers to a dimension of the social style matrix that describes how emotional people tend to get in social situations.

Responsiveness refers to a dimension of the social style matrix that describes how emotional people tend to get in social situations. 

According to the social style matrix, people's beahavior, social interactions and reactions can be categorized in terms of four different social styles: Analytical, Driven, Amicable and Expressive. The dimension on responsiveness as stated in this question involves the latter two social styles (amicability and expressiveness).