Answer:
ecosystem
Explanation:
not population, not an organism, not a community
B. The flower color in a population changes over time.
Tetracycline was the most effective true antibiotic tested against E.coli
<span>The kidney is similar to a municipal waste collection service, as both remove unnecessary and toxic waste from the communities they serve. One distinct difference would be that the waste collection service goes to the waste whereas the waste products in the blood travel to the kidneys via the blood.</span>