<span>Random fertilization adds to the genetic variation thanks to B)Fusion of sperm and ovum, each having a unique combination of chromosomes, introduces further variation. Fertilization is a process of fusion of sperm and ovum. In a random fertilization, it is expected that sperm and ovum each have a unique combination of chromosomes. Thus, the created zygote will have a unique combination of chromosomes which introduces variation.</span>
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Work is not done when you carry an object forward. You may have learnt that carrying an object and moving horizontally at a constant velocity has no work done. The truth is, there is a slight amount of work done due to overcoming air resistance in the horizontal direction.
Answer: A scientific question can be answered through an investigation. What is tested? Scientists call this an independent variable.
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