Use the information below to answer questions.
When commodity X sold for N25 per unit, 50 units of commodity Y were purchased. With an increase in the price of commodity X to N50 per unit, the demand for commodity Y fell to 20 units.

Determined the cross elasticity of demand?

• A.1.7
• B.0.6
• C.-0.6
• D.-1.7
• E.