Suppose that at prices of $5, $4, $3, $2, and $1 for product Z, the corresponding quantities supplied are 7, 6, 5,4,3 units, respectively. Which of the following would increase the quantities supplied of Z to, say, 14, 12, 10, 8, 6 units at these prices?a. Improved technology for producing Z.
b. An increase in the prices of the resources used to make Z.
c. An increase in the excise tax on product Z.
d. Increases in the incomes of the buyers of Z.

which means automation of production, so when you will have mass production at low cost it will definitely result in a decrease of product cost.
This shall consequently lead to an increase of the quantities of product Z produced because, the extra capital that comes from saving on the production costs shall be used to produce more goods.

Since production shall have not cost any extra capital, the price shall remain constant.