Guard cells. They open and close to allow for gas exchange within the leaf
Answer:
<em>The correct option is D) too few workers to support an aging population</em>
Explanation:
A positive population growth can be referred to as a situation when the population of a country is rising.
A negative growth population is referred to as a situation when the population of a country is becoming lesser. As a result of this negative population growth trend, there will be fewer workers to support the aged people. Also, there will be lesser people working for the economy of the country.
It is B, as one organism is benefiting, while the other is harmed
