312-92 Question #21: Real Exam Question with Answer & Explanation

William is the lead programmer for Gummerson, Inc., a software company located in San Francisco. Gummerson is looked upon as one of the leading software development companies for medical and health related applications. William believes that his company is so successful EC-Council 312-92 Exam because they believe in involving the user or client in the design and development of the programs. What software development methodology does Gunnerson, Inc. use when creating applications for clients?