Based on the information given this is an illustration of: The substitution effect.
Substitution effect can be defined as the way in which consumer decide to switch or change to other alternative products that are less expensive alternative.
Substituting to alternative product occur when their are rise in price of goods and services that consumer purchased in the market.
When their is decrease in price of a product, consumer tends to go for cheaper or less costly products that offers or gives the same result as the expensive one.
Inconclusion this is an illustration of: The substitution effect.
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