What is the optimum number of solutions that should be proposed to the manager to enable him / her to make the right decision?

Thanks

There are unlimited of solutions can be provided to manager to make the right decision , but in my opinion he-she needs to a good preacher to support his decision.

Regards

Thanks for posting a question which has many answers.  

In my view, though there may be innumerable solutions for any situation, the ultimate decision is taken by the management based on the best solution provided by the Manager. So it is the duty of the Manager to provide with 2-3 best solutions out of the many available, so that the management can put in its thoughts before taking a decision.

Each solution has to be analyzed by the Manager, before prioritizing the solutions. Manager should take into account all the relevant facts of the problem, like, nature of the problem, causes of the problem, steps taken or to be taken for solving the problem, data collected about the problem, resources available (including time), approach to the solution, cost associated with the solution, Benefits expected out of the proposed solutions. 

The Manager in his recommendation to the management should justify with a scientific approach the Cost Benefit Analysis of his recommended 2-3 solutions.

Thanks.

Agree on experts answers. Thanks for your invitation.

Thanks for invitation,

Unlimited numbers, but it depends on restrictions of the business environment.