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A : It makes easier to walk on slippery ...

A : It makes easier to walk on slippery muddy road if we throw some sand on it.
R : On throwing sand, frictional force of the surface increases.

A

If both Assertion & Reason are true and the reason is the correct explanation of the assertion

B

If both Assertion & Reason are true but the reason is not the correct explanation of the assertion

C

If Assertion is true statement but Reason is false

D

If both Assertion and Reason are false statements

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