B. DNA is heated to separate strands
<span>First.PCR reaction</span>
<span>epidermolysis bullosais caused by the 12th chromosome
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The Hershey and Chase experiment concluded the same by labeling the DNA of the parents with phosphorous and found out that the DNA of the offspring also bear phospho- labeled DNA, which established the fact that DNA is the heritable information source. So, your answer is B.
D, you have the right answer. Kalanchoe plants produce asexually
