A.I. Explanation:

Option 1: "Providing venues for large public events"

Explanation: This option is incorrect because the text does not mention large public events as a benefit of urban green spaces. Instead, it focuses on health benefits, aesthetic value, and environmental improvements. Therefore, this option does not align with the main idea presented in the text.

Option 2: "Reducing the cost of city maintenance"

Explanation: This option is incorrect as the text does not discuss cost reduction related to city maintenance. The benefits highlighted are primarily related to health, well-being, and environmental factors, making this option irrelevant to the main theme.

Option 3: "Enhancing the mental and physical health of residents"

Explanation: This option is correct because the text explicitly states that urban green spaces contribute significantly to the mental and physical health of the population. It provides specific examples, such as reduced stress levels and improved mood, which directly support this claim.

Option 4: "Increasing property values in urban areas"

Explanation: This option is incorrect as the text does not mention property values as a benefit of urban green spaces. The focus is on health, social interaction, and environmental benefits, making this option not relevant to the primary benefits discussed.