3) The facilities, services, and installations needed for the functioning of a community make up its A. heat island. B. infrastructure. C. suburbs. D. ecosystem services.

## Step 1<br />The question is asking for the term that describes the facilities, services, and installations needed for the functioning of a community. <br /><br />## Step 2<br />Let's analyze each option:<br />- A. Heat island: This term refers to urban areas that are significantly warmer than their surrounding rural areas due to human activities. This doesn't fit the description given in the question.<br />- B. Infrastructure: This term refers to the basic physical and organizational structures needed for the operation of a society or enterprise. This includes facilities, services, and installations needed for the functioning of a community.<br />- C. Suburbs: This term refers to residential areas situated on the outskirts of a city. This doesn't fit the description given in the question.<br />- D. Ecosystem services: This term refers to the benefits that humans obtain from ecosystems. This doesn't fit the description given in the question.<br /><br />## Step 3<br />Based on the above analysis, the correct answer is B. Infrastructure.