A research company uses a device to record the viewing habits of about 12 comma 50012,500 households, and the data collected over the past 7 yearsover the past 7 years will be used to determinenbsp whether nbsp whether the proportion of households tuned to a particular newsnews programnbsp increased. increased. Which type of observational study is described in the problem statement?

A Retrospective Study.

Step-by-step explanation:

A retrospective study is demonstrated as the kind of observational study that aims to examine the outcomes or changes observed over a span of time.

As per the question, the given problem statement demonstrates 'a retrospective study'(kind of observational study) as it aims to observe the 'viewing habits of households over a span of 7years of time' in order to determine the number of households remained tuned to a specific news program and if it increased or not. Thus, it justifies the above definition and hence, a retrospective study is the correct answer.

KN= 15 units

NM= 20 units

Step-by-step explanation: