a. They lead to biased and misleading results as members receive incentives to join the panel.
b. They require the presence of a moderator to control the discussion.
c. They lead to incorrect results as panel providers are not permitted to select panel members based on the current requirement.
d. They involve very long discussion times as panel members discuss among themselves while offering suggestions.
ANSWER: aSome critics of online panels suggest that offering incentives to join a panel leads to bias and misleading results. Others claim that they are not representative of the target population.