Answer:
Explanation:
These are arteries, which prevent the backflow of blood because the walls have little muscle to pump blood back to the heart.
The ordinary work of Sigmund Freud affected the lives of ordinary people in the 20th century because it encouraged people to search for the hidden reasons for their actions. The correct answer is A.
The tadpoles take their food from the yolk of an egg. The egg yolk is equivalent to the placenta. T<span>he </span>placenta <span>attaches itself to the uterus to provide the </span>developing<span> foetus with blood and oxygen.</span>
