Which of the Following Statements Is True Regarding Observational Data

Which of the following statements is true regarding observational data collection?

A) An observational approach results only in narrative data.
B) Numerical data is typically collected in the form of written descriptions of behavior or behavior recorded on audio or videotape.
C) The most widespread use of collecting observational data is either through scanning of purchases at stores or over the Internet when companies observe an individual's click-through behavior.
D) An advantage of this approach is that characteristics such as attitudes and reasons for the behavior can be observed.
E) This approach violates the research participant's right to privacy.