Identify the type of observational study (cross-sectional, retrospective, or prospective) described below. a research company uses a device to record the viewing habits of about 2500 households, and the data collected over the past 2 years will be used to determine whether the proportion of households tuned to a particular children's program increased. which type of observational study is described in the problem statement?

a. a prospective study
b. a retrospective study
c. a cross-sectional study