What action must be taken after adding constraints in the Solver dialog?

After adding constraints in the Solver dialog, the next step is to click the Solve button. This action initiates the optimization process where Solver evaluates the specified model and constraints to find the optimal solution. Engaging the Solve function instructs Solver to process the parameters that have been set up, utilizing the constraints defined to arrive at a suitable outcome that meets the defined objectives.

The other options represent actions that either abandon the changes made (cancel, close) or simply affirm the inclusion of constraints without executing the optimization (OK). Therefore, they do not drive the solution process forward; only the Solve button fulfills the purpose of applying the specified model and constraints to derive results.