What is a selection structure? What is the difference between a single-alternative and dual-alternative selection structure?

What will be an ideal response?

A selection structure is a control structure that indicates a decision needs to be made before it can select the next instruction to process. The decision is based on a condition specified at the beginning of the selection structure, and the next instruction to process is based on the result of that decision. A single-alternative selection structure requires one or more actions to be taken only when its condition evaluates to true. A dual-alternative selection structure requires one set of instructions to be followed only when the condition is true and a different set of instructions only when it is false.