Christkindlmarket is a holiday market that takes place every December in Chicago. From fresh baked goods to warm, sugary almonds, Gl$$hwein to ornaments, the market brings holiday cheer to the cold winter months. Interestingly, any time a customer tips a vendor, the vendor is known to ring a bell loudly for everyone to hear. What sort of motivation does this describe?

Question $30$ options:

Positive reinforcement

Negative punishment

Negative reinforcement

Positive punishment

Pavlov's human response