Answer:
Multicellular organism is the example of complexity of the natural world.
Explanation:
Multicellular organism such as human which is made of billions of cell. Each cell perform a specific function. The function of one organ is different from the other organ. For example, brain of human is made of millions of neurons which takes instructions from brain to the organs and bring messages from organs to the nervous system in the form of electrical impulses. In short every system in our body is full of complexity.
I'm not entirely sure, but I think it is B) the pulley.
People are connected to other living things such as trees and plants. Humans breathe in the oxygen the plants produce. People are connected to non living things such as stool from animals. Worms decompose the animals stool which makes the dirt richer. Humans use that rich dirt to grow plants that we consume for fuel.
