Final answer:
The Underwood Tariff Act of 1913 had a positive impact on the economy, leading to economic growth.
Step-by-step explanation:
The impact of the Underwood Tariff Act of 1913 on the economy was A. Economic growth. The Underwood Tariff Act reduced tariffs by 15 percent across all imports and eliminated tariffs for some goods, such as steel and iron ore. This reduction in tariffs encouraged economic growth by making imported goods cheaper, which stimulated consumer spending and increased business profits. Overall, the Underwood Tariff Act was intended to promote economic growth and reduce barriers to trade.