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.
Answer: is D. Mercury was used to treat many illnesses long ago, and after being deemed safe by modern doctors its use has increased in the past 100 years.
Explanation:
The correct answer is C. it takes up space and has mass.
This is something which is true of all matter. A is incorrect because it can be made of other things as well. B is incorrect because it can be found elsewhere as well. D is incorrect because it can take any form it wants - not just liquid or gas.
C your skin does not produce red blood cells your red blood sells are asexual and self produce by cell division