A huge company conducted a study to determine if the type of desk chair employees use affects job productivity, which is measured by the number of work items employees complete. The company obtained a random sample of 200 employees and randomly assigned half of them to use a traditional desk chair for a month and assigned the other half to use a large exercise ball as their desk chair for a month. At the end of the study, the company compared the job productivity between the two groups. What type of experiment is this? A. Randomized Comparative B. Randomized Block C. Matched Pairs D. Observational Study