You are involved in creating a cost estimate for software work on a traffic control system for a section of a small town. You and your team have been presented with a set of requirements for the system. You plan on using the COSYSMO model to get one of your cost estimates (you plan on obtaining two more estimates using other techniques). Which of the following is the final thing that you should do before inputting numbers into the COSYSMO model?a. assign weight factors to each requirement typeb. count the requirementsc. ensure that all requirements are at the same approximate level of granularityd. assess the testability of the requirements