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Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R) . Assertion (A) : Melting point of Boron (2453 K) is unusually high in group 13 elements. Reason (R) : Solid Boron has very strong crystalline lattice. In the light of the above statements, choose the most appropriate answer from the options given below :

1. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
2. Both (A) and (R) are correct and (R) is the correct explanation of (A)
3. (A) is false but (R) is true
4. (A) is true but (R) is false

Correct answer: Both (A) and (R) are correct and (R) is the correct explanation of (A)

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