Cobalt is mined in the Democratic Republic of Congo. Demand for cobalt comes from its use in lithium-ion batteries in electric cars, among other things. A recent report stated that the price of cobalt fell more than 40% in 2019, during which time the quantity purchased increased from 120,000 metric tons to 140,000 metric tons. This information leads you to conclude that:

Group of answer choices

a. supply is elastic

b. demand is inelastic

c. demand is elastic

d. none of the other choices is correct

e. the cross-price demand elasticity with other metals is negative