Which of the following is included in the internal psychological process?

The concept of internal psychological processes refers to the ways in which individuals mentally process information, make judgments, and develop preferences. Integration refers to the mental integration of various pieces of information, such as beliefs, attitudes, and past experiences, as consumers evaluate options and make decisions. This process can involve weighing the pros and cons of a product or service, aligning it with personal values, and considering emotional responses.

In the context of the other choices, while "Gatekeeper," "Decision Making Unit," and "Purchase decision" are related to the broader framework of consumer behavior and decision-making, they do not specifically pertain to the internal psychological processes that individuals undergo. For instance, a gatekeeper typically refers to a role that influences what information is received, while the decision-making unit identifies the people involved in the purchasing decision, and the purchase decision itself is the final outcome of the decision-making process. However, integration is inherently a mental process that reflects how individuals synthesize information and experiences internally, making it the correct choice in this context.