Because ideas about evolution by natural selection have never been proven false, what term can be used to describe evolution by natural selection

Because of the ideas about the evolution by natural selection have never been proven false, technically, the term "natural selection" is the best one to describe evolution. Since evolution is considered to be the change of heritable traits that natural selection is all about.

a catalyst

Explanation:

Catalyst is a substance that influences the rate of reaction without being consumed in the reaction. They increase the rate of reaction by decreasing the activation energy of the reaction. In biological system, enzymes are referred to as biological catalyst or biocatalyst. They are generally protein in nature and are very specific for their substrate. They also increases the rate of biological reaction by forming enzyme-substrate complex.

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