Answer:
C. Producers would have less material for making food.
Explanation:
An ecosystem can be defined as the natural living habitats of both living and non-living organisms, in which they interact with one another. Essential services such as plant pollination, water purification, nutrient cycling etc that are being provided by the ecosystem are really very vital, important and useful for the sustenance of life, both for humans and enhances social welfare.
A list of the types of organisms in an eco pyramid are;
I. Producers: these are autotrophs or self-feeders such as plants.
II. Primary consumers: these are herbivores that typically feed on plants such as a goat or deer.
III. Secondary consumers: these consists of carnivores that typically feed or eat flesh such as lion, tiger, cheetah, etc.
IV. Tertiary consumers: these are higher predators such as humans that aren't normally fed on by other organisms in the ecosystem.
In Biology, producers are the living organisms that are capable of manufacturing their own food and as such can provide energy or food for the other living organisms (consumers) in a food chain. Thus, producers are mainly known as the foundation of a food chain and are at the top.
A producer gets energy from the sun and converts it into food. The cells found in producers are capable of converting the energy received directly from the sun into food through a process generally referred to as photosynthesis, converting carbon dioxide from the air, water from the soil, minerals and energy from the sun into organic nutrients.
Hence, if the amount of atmospheric carbon dioxide were decreased, the most direct effect on the ecosystem is that producers would have less material for making food.