Question

reading comprehension practice test
while the terms green and sustainable are often considered synonymous, in that they both symbolize nature, green does not encompass all that is meant by sustainability, which can be defined as minimizing the negative impacts of human activities on the natural environment, in particular those which have long - term and irreversible effects. some elements of green design may be sustainable too, for example those which reduce energy usage and pollution, while others; such as ensuring internal air quality, may be considered green despite having no influence on the ecological balance.
the examples of green and sustainable designs given in this paragraph show that _?_
for the purposes of this paragraph, the terms green and sustainable have the same meaning
some designs are termed green, even though they are not sustainable
designs must be sustainable in order for them to be described as green
some sustainable designs are green, while others are not

Explanation:

The text states that while "green" and "sustainable" are often seen as synonyms, green doesn't cover all aspects of sustainability. It gives examples of how some green - design elements can be sustainable (like energy - usage reduction), while others may be green but not sustainable (like ensuring internal air quality). This shows that some sustainable designs are green and some are not.

Answer:

Some sustainable designs are green, while others are not