In accordance with Newton's first law, the characteristic of a moving object that remains constant when other forces act on it is its mass. Unlike speed, shape, or size, mass does not change due to external forces. Understanding this principle is crucial in physics to predict the behavior of objects under various forces. ;
According to Newton's First Law, the characteristic of a moving object that remains constant in the absence of external forces is its mass. Mass is an intrinsic property that does not change regardless of speed or external influences. Therefore, the correct answer to the question is B. mass .
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