<span>Sedimentation - uses solutions of lower specific gravity than the organisms, which concentrated in the sediment. This technique is recommended for general diagnostic laboratories because it is easy to perform and less prone to technical errors.
Flotation - this technique uses solutions of higher specific gravity than the parasitic organisms so the organisms float and the debris sinks producing a cleaner material while the disadvantage is that walls of cysts and eggs collapse that may blocking its identification.<span>
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The answer is A. a light wave
C and D both need water as a medium and sound needs air to vibrate in order to travel. light, on the other hand, does not need a medium
Human egg cell
But human egg cell is the one of the largest cells in the human body that can be seen with naked eye. i.e we are able to see it without the help of a magnification device. The size of this cell is about 0.12 mm in diameter.