Matrix are within the inner membrane of the mitochondria.
<h2><u>Answer</u> :</h2>
The correct option is A. If a dominant allele is present, the recessive allele won’t be seen.
The dominant allele is the one which appear, and the recessive one isn't shown.
For example - If a person has 2 alleles of eye colour as B ( black ) and b ( brown ), in which black is dominant and the brown one is recessive, then the person will have black eye colour because only dominant allele shows its characteristics.
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<span>B. A virus that causes a common cold
Hope this helps!
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