Question

work conducted near flammable gases or explosive materials must be conducted with ____ tools.
spark-resistant
mushroomed
tethered
field-installed

Explanation:

When working near flammable gases or explosive materials, the main concern is to prevent sparks that could ignite these substances. Spark - resistant tools are designed to minimize the generation of sparks during use. Mushroomed tools refer to tools with a deformed end (like a mushroom), which is not relevant to safety near flammables. Tethered tools are tools attached by a cord, mainly to prevent them from being dropped, not to prevent ignition. Field - installed tools are tools installed on - site, which also has no direct relation to preventing ignition from sparks.

Answer:

Spark - resistant