Question

1. environmental bioremediation using bacteria is least effective on ______.

○ heavy metals
○ tar
○ antifreeze
○ crude oil

Explanation:

Bacterial bioremediation works by microbes breaking down organic compounds; crude oil, tar, and antifreeze are organic, while heavy metals are inorganic. Bacteria cannot break down inorganic heavy metals effectively, making this method least effective on them.

Answer:

A. heavy metals