Constrained optimization methods are complex mathematical formulas and algorithms that are used to predict the success of projects, the variables within projects, and tendencies to move forward with selected project investments. 1 is incorrect because benefit/cost ratios examine the cost to benefits of multiple projects. 3 is incorrect. This approach compares the current project to others to determine the best choice of action. 4 is also incorrect. Prioritization is the priority assigned to multiple existing projects within an organization.