What step will be most effective for a manufacturer that wants to reduce the human costs of extracting the minerals it uses in its smartphones?

1. committing to only mining minerals in the United States
2. switching to using gold instead of tungsten in its products
3.verifying that child labor was not used in mining these minerals
4. decreasing the prices of its products

The most effective step for a manufacturer that wants to reduce the human costs of extracting the minerals it uses in its smartphones would be option 3: verifying that child labor was not used in mining these minerals. By ensuring that child labor is not used in mining, the manufacturer can not only address the ethical concerns associated with child labor, but also create a safer and more sustainable supply chain. This can be achieved through certification schemes, due diligence programs, or responsible sourcing initiatives that trace the origin of minerals back to their source and monitor the mining practices involved. Committing to only mining minerals in the United States or switching to using gold instead of tungsten in its products may reduce the environmental or geopolitical risks associated with mining, but may not necessarily address the human costs of mining. Decreasing the prices of its products may provide short-term benefits to consumers but may not necessarily address the underlying issues associated with mining practices.