Before a star is a star, it is an enormous cloud of gases. At the start, wisps of gas and drifts of dust collect, their gravity drawing them together. As more stuff gathers, its combined gravitation grows stronger. Eventually the cloud pulls itself into a massive ball of material.

—A Black Hole Is NOT a Hole,
Carolyn Cinami DeCristofano

Describe the cause-and-effect relationships in this passage that lead to the formation of a star.

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