Mars bc none other planet showed signs of life
He cross pollinated the pea plant with another pea plant that had a different feature. The point is that he CHOSE the plant himself with that specific feature, it was in his control.
The correct answer is water
Stars are formed when a large cloud of gases containing hydrogen and helium heat up and collapse into a mass of hot sphere due to the force of gravitational pull. These hot gases inside the hot massive sphere are subjected to immense pressure due to the gravity. The atoms of these gases collapse and fuse with the neighbouring atoms to undergo the process of atomic fusion. This process releases so much energy that the hot mass of sphere starts to glow and become a star.