Answer:
The controlling idea of the paragraph is: "Social media has a valid purpose as an inexpensive, creative marketplace."
Step-by-step explanation:
The controlling idea of a paragraph is the main point or central idea that the author wants to convey through the paragraph. It ties together all the sentences and details within the paragraph and helps the reader understand the purpose of the paragraph. In the given paragraph, the controlling idea is that social media has a valid purpose as an inexpensive, creative marketplace. The paragraph talks about how social media is often criticized for meaningless posts and rants, but it also serves as a platform for entrepreneurs to advertise their products at a low cost to a wider market.