Answer:
A group of bacteria that accumulate in layers and secrete a protective extracellular material. (Option A)
Explanation:
Biofilm is defined as one or more types of microorganisms collectively grow in different places. Organisms that form the biofilm include protests, fungi, and bacteria.
Dental plaque is an example of a biofilm. It is a known buildup of slimy bacteria that forms on the teeth surface. Biofilm can grow on different surfaces such as animal tissues, plant tissues, minerals, metal, etc.
Natural acids because chemicals erode rocks in chemical weathering
<span>Alleles are each of two or more alternative forms of a gene that are found at the same position in a chromosome. Traits on the other hand, are the characteristics that are defined by genes. So the combination of alleles for a gene is what manifests itself into a trait.</span>