Mutation is a source but it is not the main source after it comes recombination in which 2 chromosomes with “normal” survival are taken from natural population of Drosophila and combined. Then comes immigration of genes in which the new chromosome mix in with different gene frequencies.
The correct answer is B. Sensitive period
Explanation:
In development, the sensitive period refers to a lapse of time in which organisms are more susceptible or receptive to stimuli and therefore during this time there can be great advances in development. Additionally, different from critical periods sensitive periods do not imply irreversible consequence if the stimuli are not presented. For example, in human beings from birth to the age of 6 years, children are more receptive to learn and acquire certain skills such as learning a new language if exposed to it and therefore this can be considered as a sensitive period. Considering this, it can be concluded the definition presented refers to the Sensitive period.
C is the proper answer. They have been reduced by using unleaded gasoline because lead can harm the air and water we breathe, so using less of it will help reduce the pollution being caused by it.
