Answer: B. DNA polymerase checks for errors in base pairing as it helps new DNA strands form.
Explanation: DNA polymerase is an enzyme that catalyzes the synthesis of a new DNA strand from a DNA template. This process is known as replication. During replication, DNA polymerase rejects incorrect bases before the phosphodiester bond is formed because it has a 3' -> 5' exonuclease activity that double checks every nucleotide that is added to the growing strand. This check allows the enzyme to remove a newly added mismatched base pair.
Neither of these are minerals, B.
Its not A because, they are not natural materials but instead made up of natural materials, like a rubber tree.
Its not C because, like I said, plastic is made from rubber trees, this garentees it doesnt have a crystal structure.
Its not D because, concrete is not a mineral and has indefinite composition.
Answer:
I believe the answer is plasma membrane.