Which statement best describes trends in safety in underground and surface mining in the united states?

Explanation:

The process of extracting valuable minerals from the Earth, generally from an ore body or placer deposit is known as mining. Globally the mining sector is full of risks.

But with proper scrutiny on safety of underground and surface miners, the sectors of United States has improved rapidly. Underground miners should carry gas detectors to measure dangerous gas like methane, that are explosive. Surface miners must use hearing protection while working in loud noise areas.

Risk rate values, techniques of fire detection and suppression, flaming source, and other variables are focused for the safety purposes of miners.

the answer is "a.) well–developed vascular system."

explanation: