Question

why are debates such as one about the color of a dress so popular? complete the sentences. some experts think posts go viral because people are naturally competitive. although debates like the one about the color of a dress might not be important, they have wide appeal because many people enjoy arguing about a dropdown with options: carefree topic, scientific idea, personal story

Explanation:

The debate about the dress color is a light - hearted, non - serious topic. "Carefree topic" fits as these debates aren't important or scientific, and people enjoy arguing about such relaxed topics. "Scientific idea" is incorrect as the dress color debate isn't scientific, and "personal story" is wrong as it's a general topic, not a personal anecdote.

Answer:

carefree topic