Non-random sampling includes

No one should force to participate in a study against his or her will, this refers to voluntary participation.  

Sampling frame is the complete list of all members of the population. 

Deductive reasoning moving from specific observations to broader generalizations and theories.

Stratified random sampling refers to the:

None -Random Probability Sampling allows generalization.

Evaluating idea is a one process to selecting the research question.

The purpose of the literature review is to:

An abstract  is refer to the objective of research.

Generalization is essential to represent the sample.