Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Walras' law states that the value of aggregate excess demand for all markets is zero.
Reason R: If (K-1) markets are in equilibrium, then the market for good K will automatically have demand equal to supply.
In the light of the above statements, choose the most appropriate answer from the options given below: