A console game, ZOMBIES!, has come out recently. It sells for $60. Which of these might lower the price of the game?
A negative article about the game from a well-known reviewer, causing sales to drop
A positive article about the game from a well-known reviewer, causing sales to rise
A significant increase in the cost of a competitor's game, U.S. Zombies
A significant rise in the cost of gas, causing shipments of the game to slow down