A star currently has a surface temperature of 10,000K and a luminosity of 200L_☉ Over time, it expands and cools, decreasing its temperature while maintaining its luminosity. Which phase of the star's lifecycle is it most likely entering?

A star that expands while its surface temperature decreases is moving toward the red giant phase. Its luminosity can remain about the same because its larger surface area compensates for the cooler surface. A white dwarf is small and hot, while a red dwarf is a low-mass main-sequence star.

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