Researchers have found that before buying a new car, consumers tend to look at ads for all makes and models of cars. However, once having purchased a car, consumers tend to read only ads for the kind of car they purchased. This tendency best illustrates the phenomenon known as:.

selective exposure

Explanation:

Selective exposure -

It is also known as confirmation bias or congeniality bias .

The practice is used in the communication and media research ,

Where the people tries to follow their own , predefined views and avoid any  opposing views, is referred to as selective exposure .

Hence , from the given scenario of the question ,

As the person buys the car , then he tries to ignore any contradictory information against the car .

Therefore , the correct answer is selective exposure .