What is the best description of the grass seed that is described in this scenario?

The Grass seed is a Product with elastic Supply ,  a Product which demand goes up and down as the price rise and fall

In the beginning the price of the seed was high with a high demand , so many people want to supply it. But as the supplier increase , the product became too much on the market so the demand drop. To attract more demand, the supplier lower the price and supply less.

The president's only official legislative duty is to sign or veto bills.