Consider the following statements: Statement-I: Giant stars live much longer than dwarf stars. Statement-II: Compared to dwarf stars, giant stars have a greater rate of nuclear reactions. Which one of the following is correct in respect of the above statements?
A.Both Statement-I and Statement-II are correct and Statement-II explains Statement-I
B.Both Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I
C.Statement-I is correct, but Statement-II is incorrect
D.Statement-I is incorrect, but Statement-II is correct✓ Correct
Explanation
Statement-I is incorrect, but Statement-II is correct. Giant (massive) stars actually have much SHORTER lifespans than dwarf stars. For example, massive O-type stars live only a few million years, while red dwarfs can live for trillions of years. This is precisely because giant stars have a much greater rate of nuclear fusion reactions due to higher core temperatures and pressures, which causes them to burn through their hydrogen fuel rapidly. So Statement-II is correct and is in fact the reason giant stars live shorter, not longer.
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