Olive Oil Producers Want to Sell More Olive Oil at a Higher

Olive oil producers want to sell more olive oil at a higher price. Which of the following events would have this effect?

A) an increase in the price of olive oil presses
B) a decrease in the cost of transporting olive oil to markets
C) an increase in the price of land used to plant olive trees
D) research finds that consumption of olive oil reduces the risk of heart disease