Natural selection causes A. changes in allele frequencies within a population. B. changes in the mechanism of inheritance. C. the inheritance of acquired characteristics. D. a decrease in reproductive fitness in a population. E. changes in an individual's genes.

Natural selection causes change in allele frequencies within a population.          

So option A is correct one.

Explanation:

Natural selection generally  work  on an organism’s phenotype, or observable features. Phenotype is often largely a product of genotype (the alleles, or gene versions, the organism carries). When a phenotype produced by certain alleles helps organisms survive and reproduce better than their peers, natural selection can increase the frequency of the helpful alleles from one generation to the next – that is, it can cause microevolution.

the  frequency of a wave represents  the number of wavelengths that pass a specific point per second. the unit for  frequency  is hertz (hz).

happy to

pls mark as brainliest

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.