The correct answer for this question would be repressible enzymes. Repressible enzymes are those which bind to the operator, and then block the attachment of RNA polymerase, which therefore prevents the transciption of genes. From this, we know that these are the types of enzymes that are synthesized in an environment where an operon is needed to code for enzymes that synthesize a protein from precursor amino acid molecules.
Soils develop different horizons due to the amount of weather that is being exposed to each individual layer. What separates one horizon from another is the properties that make up each layer.
Conjugation is the process name !
