Answer:
B I think sorry if I am wrong
A star is formed within the clouds of dust. These clouds of dust are scattered throughout the galaxy. These dust clouds are called as nebula. The turbulence inside the dust clouds rise to form knots. These knots along with sufficient mass causes gas and dust to collapse with the help of gravitational force. These sequence of steps leads to form a star.
Her conclusion is invalid because using sand instead of soil slows down plant growth. Fertilizer, on its own, does not 'greatly' increase the size of the plant.
The correct way to do this experiment would be to keep all other parameters same, except the fertilizer. This will give her accurate results.
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