Rightward supply shift from increased market supply

Steps:

• Recall that a rightward supply curve shift means more quantity supplied at every price.
• Identify non-price determinants of supply: input costs, technology, number of sellers, taxes/subsidies.
• Evaluate each option against these determinants to find the one increasing overall supply.
• Confirm the option that adds more producers without changing individual firm behavior.

Why B is correct:

• Law of supply: More firms in the industry raise total output at each price level, shifting the market supply curve rightward.

Why the others are wrong:

• A: Higher labor costs increase production expenses, shifting supply leftward.
• C: Price change causes movement along the existing curve, not a shift.
• D: Indirect tax raises effective costs, shifting supply leftward.

Final answer: B