True, sleep problems indeed are a quite often occurence among children as well as adults - they do occur quite often but don't necessarily occur all the time for people to whom it does happen. At the same time, when someone suffers from sleep problems, this doesn't necessarily mean that he cannot sleep at all.
Answer: D. Quadriceps
Explanation:
The Quadriceps are the main muscles in the thigh and are some of the most powerful in the body due to their use in anything that requires the movement of the legs. Without the quads, we would be unable to walk, talk more of run.
The Quads along with the rest of the legs, are very important when it comes to high jump and long jump but the Quads are specially important when one needs to leap in these events because it is estimated that the leaping power needed is 80% produced in the quadriceps.
It goes out the uterus in a period.