A.I. Explanation:

Option 1: "The power of the web can be utilized to offer surprisingly large rebates to a sizable number of people for things they actually want to buy."

Explanation: This option accurately reflects the main idea of the text, which discusses how the internet enables significant discounts for consumers. The term 'rebates' is paraphrased from 'surprisingly large discounts,' and both phrases convey the same concept of reduced prices. The text emphasizes the ability of the web to connect many people with desirable deals, supporting this option's correctness.

Option 2: "It's expected to grow 138 percent to $2.9 billion this year in the US alone, according to Local Offer Network."

Explanation: This option is incorrect because it misstates the expected growth figure. The text specifies that the growth is to $2.7 billion, not $2.9 billion. This discrepancy in the numerical value makes the statement factually incorrect, as it contradicts the information provided in the text.

Option 3: "Recommend the deal to two friends and get three $10 credits, used towards a deal at a local restaurant that gives $40 worth of food and drink for just $20 — a free meal."

Explanation: This option is incorrect because it inaccurately states the number of credits received. The text clearly states that recommending the deal to two friends results in two $10 credits, not three. This misrepresentation of the details makes the option factually incorrect.

Option 4: "A $50 haircut will set you back a mere $25 when purchased with the click of a mouse on a group buying website."

Explanation: This option is correct as it directly quotes the text, which states that a $50 haircut costs only $25 when bought through a group buying website. The phrase 'set you back a mere $25' is an exact match to the text, confirming its accuracy and relevance to the question.