Ms. Franklin conducted a survey with her class to identify stimuli that might serve as reinforcers. All of the students in her class indicated that extra recess time and pencils would be some things they would like to earn. She then collected baseline data on the number of math problems each student correctly completes during seatwork time. Following this, she told her students they can have 5 minutes of extra recess if they complete 5 more math problems during seatwork time today than they did yesterday. Each day, she increased the number of math problems the students needed to complete to earn extra recess. She kept a graph of the results, which showed a steady increase in the number of problems completed correctly. What can be said about what she has done?
a) She has demonstrated that extra recess functions as a reinforcer for work completion.
b) She has demonstrated that pencils have no effect on work completion
c) She has demonstrated that pencils are a reinforcer for work completion.
d) She has demonstrated that extra recess functions as an NCR for work completion.
e) She has not demonstrated anything

As per the question, option A i.e. 'She has demonstrated that extra recess functions as a reinforcer for work completion' most appropriately displays what Ms. Franklin has done to encourage the students to get the desired behavioral outcome from them in the from of 'steady improvement in number of students solving no. of maths problems correctly'. She offers the 'extra recess time along with the pencils' which functions as positive reinforcer that stimulates or reinforces the probability of the intended outcome or behavior and elicit the desired behavior from the students. Thus, option A is the correct answer.