Question

The most vital process for the existence of life on earth is
A) Communication in animals
B) Photosynthesis in plants
C) Reproduction in plants and animals
D) Respiration in animals

Answer 1

Hint: Plants produce their own food and pass their energy to humans as we eat plant nutrients. Plants produce clean air that humans can breathe. It also helps plants to grow, which provides food for humans.

Complete answer:
Photosynthesis is the most critical mechanism for the survival of life on Earth today. It is the only mechanism that releases oxygen from water and produces food, on which all animals depend directly or indirectly. Furthermore, aerobic respiration is the most essential respiratory mechanism for most organisms' survival.

The mechanism by which organisms transform light energy into chemical energy is known as photosynthesis. In chlorophyll containing plants, algae, and cyanobacteria, the most common and essential type of photosynthesis occurs.

These species absorb solar energy and transform it to chemical energy contained in carbohydrates molecules by using carbon dioxide and water. As a by-product, oxygen and water are released.
Photosynthesis by plants is the most vital process for the existence of life on earth because photosynthesis helps to maintain the equilibrium position of $O_2$ and $CO_2$ in the atmosphere.

Photosynthesis is a process through which plants and other organisms transform light energy into chemical energy, which is then released to power the organism's metabolic activities through cellular respiration.

The most vital process for the existence of life on earth is Photosynthesis. So, option B is the correct answer.

Note: Photosynthesis roles
- It is the atmosphere's primary source of oxygen.
- It helps to keep the carbon cycle going between the atmosphere, the oceans, plants, and animals.
- It helps to maintain the symbiotic relationship between plants, humans, and animals.
- It has an effect on the majority of life on Earth, either directly or indirectly.
- It is the main source of energy for the majority of trees and plants.