Which of the Following Is False of Possible Hidden Variables

Multiple Choice

Which of the following is false of possible hidden variables in correlations?

A) Hidden variables can be the true cause of an outcome
B) The effects of hidden variables can always be controlled and fully accounted for after the data have been collected.
C) When hidden variables exist, they can either be directly or indirectly associated with the target variable.
D) All of the above are true.