Market research business Neilsen tracks consumer behavior across several areas and within more than 100 markets. For example, their Homescan research tracks consumer purchasing patterns. By recording scanner data the data collected when a consumers purchases are scanned in at the checkout -- Neilsen can determine what is being purchased, when and where it is being purchased, and what it is being purchased with. This affords them tremendous insights into consumer behavior. This is an example of:

A. Direct Observational Research

B. Indirect Observational Research

C. Commercial Secondary Data

D. Public Secondary Data