The Marketing Managers of Brand Z Shoes Have Clearly Defined

The marketing managers of Brand Z Shoes have clearly defined their research problem as "If we increase our promotions expenditures,by what percentage will it increase sales?" They have also decided that they need primary data to answer this question,and to collect these data they will use _______ research.

A) Qualitative
B) Mechanical
C) Exploratory
D) Quantitative
E) Case-based