19. The Prince Edward Island Tourism Board wanted to understand why there was such a large increase in visitors to PEI last year. They conducted preliminary research with visitors to get some ideas. After that, they ran a new ad campaign for several weeks, which asked interested viewers to call a 1-800 number for more information. They carefully tracked the number of calls to this number. This is an example of research, followed up by research. A. primary; secondary B. causal; descriptive C. descriptive; causal D. exploratory; causal