In online surveys, calculating response rates can be a problem due to the:
A. close interaction of researchers with data collection vendors to identify and target participation from specific groups.
B. inadequate number of individuals in organized panels of respondents.
C. possibility of recruitment of participants outside the official online data collection vendor.
D. ban on use of radio buttons, pull-down menus for responses, and the use of visuals.
E. application of graphics and animation.
