Answer:
It would be the forest floor.
Explanation:
The forest floor is the lowest level, and therefore is covered by things above it.
I believe it’s A (captive breeding)
When two protein chains combine to form an active protein, the structural level is quaternary.
<h3>What is a quaternary structure?</h3>
The quaternary and tertiary structure of a protein is the tridimensional shape of the protein, which involves protein domains.
The quaternary protein structure refers to the different arrangements generated by different protein subunits.
The primary structure of a protein involves its amino acid sequence, whereas the second structure involves protein chains.
Learn more about quaternary structure here:
brainly.com/question/5286438
