What should not be used when preparing poached eggs?

When preparing poached eggs, using boiling water is not recommended because the vigorous bubbles and agitation can cause the eggs to break apart and result in an unappealing presentation. Poaching requires a gentle cooking method to ensure that the eggs cook evenly while maintaining their shape.

Simmering water, on the other hand, is ideal for poaching as it provides a stable, controlled environment with gentle movement that helps the eggs cook without disruption. Cold water is not suitable because it would not cook the eggs properly, and while steaming can be a method used for certain dishes, it is not traditionally associated with poaching eggs. Thus, the correct answer indicates the method that would lead to undesirable results when poaching eggs.