A company is set to launch a new product line. At first, only the brand's logo is displayed in various media, without any explanation of what the brand is or what the brand does. Greater familiarity with the logo, in and of itself, tends to make consumers like the brand more. This strategy is known as:

Mere exposure effect.

Explanation:

Just as the name sounds "mere exposure", this is explained to be a phenomenon where trust is build on familiarity. Constant usage, constant familiarizing with a particular person, object or product makes a person trust it more than others or its substitutes. This effect according to research and natural order is seen to be psychological that is why the company in the case above used only their logo in all media sampling and other adverts first just to trap the minds of those familiar with their brands before the advert. Simply here, a user can easily trust to buy the new product based on the older products.