Given below are two statements : one is labelled as Assertion \((A)\) and the other is labelled as Reason \((R)\). Assertion \((A)\): Osteoporosis is characterised by decreased bone mass and increased chances of fractures. Reason \((R)\) : Common cause of osteoporosis is increased levels of estrogen. In the light of the above statements, choose the most appropriate answer from the options given below:

1. A Both \((A)\) and \((R)\) are correct but \((R)\) is not the correct explanation of \((A)\)
2. B \((A)\) is correct but \((R)\) is not correct
3. C \((A)\) is not correct but \((R)\) is correct
4. D Both \((A)\) and \((R)\) are correct and \((R)\) is the correct explanation of \((A)\)