I think it is natural selection. genetic variation also could be a factor for physical variation over the years.
The answer is D. All of the above
An anaesthetic used when giving birth to produce loss of pain around the waist area
This is an incomplete question. Without further information, it's impossible to answer :( But here's some ideas . . .
Guidelines for narcolepsy - Put your hair in a braid and hang from the wall so you don't fall down
Walking: Try putting 1 foot in front of the other
Answer: d
Explanation:
Because it's quick easy and efficient so you can have easy access to it and all you use is your toes and calves.
