Answer:
a reduction in the price of the good
Explanation:
A supply curve will shift to the right if the sellers increase the amount of goods sold in the market.
When the price of that particular good is decreased, the amount of profit that the sellers can get from selling the goods will also decreased. So in response, the Sellers will reduce the amount of goods sold in the market (at least until the selling price bounced back again). This will cause the supply curve shifts to the left.