The Delphi method used for forecasting:
a) Obtains forecasts through a comparative analysis with a previous situation.
b) Uses measures that are believed to influence the behavior of a variable that the researcher wishes to forecast.
c) Uses a single measure that weights multiple indicators and provides a measure of overall expectation.
d) Uses a panel of experts, whose identities are typically kept confidential from one another, to respond to a sequence of questionnaires.