Sponsored links are links that have been paid for in order to bring them to the first positions when the engine returns the results of the search. Organic links are links that have not been paid for. Your answer is D.
Experiments. ...
Surveys. ...
Questionnaires. ...
Interviews. ...
Case studies. ...
Participant and non-participant observation. ...
Observational trials. ...
Studies using the Delphi method.
A cell reference is also called a cell address.
