The income elasticity of demand for jewellery is 2. Other things being equal, a 10% increase in consumer income will

The income elasticity of demand for jewellery is 2, and there is a 10% increase in consumer income.

$$2 = \frac{\text{Percentage change in quantity demanded}}{+10\%}$$

$$\text{Percentage change in quantity demanded} = 2 \times (+10\%)$$ $$\text{Percentage change in quantity demanded} = +20\%$$

Since the income elasticity is positive (2), jewellery is a normal good. An increase in income leads to an increase in quantity demanded.

A 10% increase in consumer income will lead to a 20% increase in the quantity of jewellery purchased.

The correct option is D.
D) increase the quantity of jewellery purchased by 20%.

The final answer is $\boxed{\text{D}}$