Hello Aspirant,
I hope you are doing well.
The strands are drawn together and twisted to form a yarn.
The process of extracting and twisting fibres from a clump of cotton is known as spinning (or wool, silk, etc.). Thus, the tiny fibres combine to form yarn, a length of twisted thread.
Since fibres come together to form a solid whole when they are spun, the fibre must be spun. It keeps them together as a coherent group.
I hope this helps.
Good Luck
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