Which technique uses constructive feedback effectively

The sandwich feedback consisting of Compliment,Criticism

Explanation:

Constructive  criticism : refers to  the process of offering good and well-reasoned opinions about other people's work, usually involving both negative and positive comments, usually in a friendly tone rather than an harsh tone.

Constructive Compliment: this refers to a healthy blend of praise for suggestions and achievement for a more better improvement.

In order  to give a good constructive feedback managers have understand the art of having hard conversations with their employees and offering them nice praise in the right way.