There are various influences that affect consumers’ decisions. The six categories of influences are:

1. Demographic factors such as age, gender, income of consumers,
2. Psychological forces such as perceptions, attitudes, learning abilities, personalities of consumers,
3. Social forces such as families, friends, and reference groups of consumers,
4. Situational factors such as physical surroundings, social surroundings, time perspective, reason for purchase and the buyer’s monetary conditions,
5. Environmental factors such as economic conditions, political circumstances in the country of a consumer and
6. Marketing factors

Thus, the correct answer is D.