A.I. Explanation:

Option 1: "Intrinsic motivation is more common than extrinsic motivation."

Explanation: This option incorrectly asserts a comparison between intrinsic and extrinsic motivation, suggesting that one is more common than the other. The text does not provide any information about the prevalence of either type of motivation, focusing instead on defining both types. Therefore, this statement is not supported by the text.

Option 2: "People are motivated to work harder for two different kinds of reasons."

Explanation: This option accurately paraphrases the main idea of the text, which introduces the two types of motivation: intrinsic and extrinsic. The phrase 'two different kinds of reasons' effectively captures the essence of the topic sentence, as it encompasses both intrinsic and extrinsic motivations without favoring one over the other.

Option 3: "There may be surprising effects of extrinsic motivation on intrinsic motivation."

Explanation: This option introduces a new idea about the effects of extrinsic motivation on intrinsic motivation, which is not mentioned in the text. The text focuses solely on defining intrinsic and extrinsic motivation rather than discussing any potential interactions or effects between the two.

Option 4: "Children work better when they are offered something nice in the end."

Explanation: This option implies a specific scenario related to extrinsic motivation, suggesting that children perform better when rewarded. However, the text does not limit the discussion to children or imply that extrinsic motivation is the only factor for better performance. It fails to capture the broader concept of motivation types presented in the text.