The best answer would probably be observation because a hypothesis and theory is not always reliable. an observation describes what IS happening during the experiment.
Answer:
Carbon dioxide from the air is used to produce food for plant growth. Carbon moves from plants to animals when animals eat the plants. Also, Carbon moves from living things to the atmosphere. Each time you exhale, you are releasing carbon dioxide gas (CO2) into the atmosphere.
The burning of fossil fuels also releases carbon dioxide into the atmosphere.
A. Decreasing amount of energy needed to start a reaction.
Answer:
Antonie van Leeuwenhoek used single-lens microscopes, which he made, to make the first observations of bacteria and protozoa. His extensive research on the growth of small animals such as fleas, mussels, and eels helped disprove the theory of spontaneous generation of life.
Explanation: