A locally owned spa, Alexanders, is interested in adding the tea room which not only offers specialty teas but organic lunch menu. In order to find out how many of its regular customers would be interested in such an addition Alexanders sent out short email questionnaire. One question asked its customers to indicate how much they spend monthly on all natural, organic products. These data are....
A. Categorical
B. Cross-sectional
C. Transactional
D. Experimental
E. time series