Which of the Following Is FALSE

Which of the following is FALSE?

A) Sampling control concerns the researcher's ability to direct the inquiry to a designated respondent and to get the desired cooperation from that respondent.
B) Random digit dialing and "Plus-One" sampling are both attempts at overcoming the sampling bias of unlisted numbers.
C) The heads of households with unlisted telephone numbers are less likely to be employed in an unskilled or semi-skilled job than heads of households with listed telephone numbers.
D) All of these are false.
E) None of these are false.