Which of the Following Would Be Most Likely to Produce

Which of the following would be most likely to produce the fastest learning that is also resistant to extinction? Start with:

A) a variable reinforcement schedule and then shift to a continuous reinforcement schedule one the behaviour has been learned.
B) a fixed reinforcement schedule and then shift to a variable reinforcement schedule once the behaviour has been learned.
C) continuous reinforcement and then shift to a fixed reinforcement schedule once the behaviour has been learned.
D) continuous reinforcement and then shift to a variable reinforcement schedule once the behaviour has been learned.