Question

The law of demand, assuming other things to remain constant, establishes the relationship between :
(a) income of the consumer and the quantity of a good demanded by him
(b) price of a good and the quantity demanded
(c) price of a good and the demand for its substitute
(d) quantity demanded of a good and the relative prices of its complementary goods

Answer 1

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(a) income of the consumer and the quantity of a good demanded by him ✔️

Answer 2

Option b is the correct answer.

The law of demand, assuming other things to remain constant, establishes the relationship between price of a good and the quantity demanded.

1. It is price which if falls then demand rises and vice versa.  
2. Income, price of substitute goods, price of complementary goods, taste and preferences etc. are other factors which are responsible for shift in demand whereas price leads to increase and decrease in demand.