Consumer behaviour is an external factor that enabled addition of special effects in advertisements and tracking of responses of customers over websites.
The social media factor has widened horizons for advertisers and has helped immensely in creation of new
communications media.
Consumer behaviour is the study of how individual customers, groups or organizations select, buy, use, and dispose ideas, goods, and services to satisfy their needs and wants. It refers to the actions of the consumers in the marketplace and the underlying motives for those actions.
Therefore, the correct answers are consumer behaviour and social media respectively.
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