Its B. out of common knowledge and experience <span />
Since there are 46 all together, each parent donates 23.
Hope this helped!
<h3>The blood in the pulmonary artery is going to the heart to collect oxygen, and therefore has a low content of oxygen. So, the blood in the pulmonary artery is a violet colour because it has low oxygen. The blood in the pulmonary vein is oxygen rich, and so it gives a scarlet</h3>

The human movement is 4
exercises that use body weight is 5
contracting muscle is 12
holding a contraction is 8
decreasing the angle is 6
strengthening is 3
increasing is 7
lengthening of a muscle is 10
maximum amount of force is 1
isolating muscles is 15
undesirable movements is 14
shortening muscles is 9
sustained contraction is 2
opposing action is 13
increasing the weight is 16