Material Z is highly dangerous: there are $500$ litres in stock and there is no further use for it$.$ The company will have to pay $4$ per litre to have it removed. The current market purchase price is $12$ per litre and the material in stock originally cost $10$ per litre. A potential project needs $600$ litres of Material Z$.$

What is the relevant cost for Material Z in the project?

A$.$

$500$

B$.$

$2,000$

C$.$

$8,00$

D$.$

$3,500$