Explanation:
In thermoplastics, the arrangement of monomeric units is linear and in thermosetting plastics, it is cross-linked. Thermoplastics are usually soft, weak and less brittle, so can get soften on heating and stiffen on cooling. They can be melted, remoulded and recycled easily.
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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