In Which of the Following Scenarios Is It Most Likely

In which of the following scenarios is it most likely that voluntary consent to submit to a search will not be found?

A) A suspect is taken into custody and then consents to a search of his vehicle
B) A suspect grants permission after being asked once but is not informed that he can refuse
C) A suspect gives verbal permission to search his bag but then refuses to sign a consent form
D) A suspect with a moderately long criminal record is asked once for permission and grants it