Answer: there are no mistakes that I've noticed and if you wrote that then good job.
Explanation:
Cancellous bone is sometimes called a dense bone.
So the answer would be A
The answer is: [B]: They use different nucleotide bases.
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Specifically, DNA replication uses thymine; whereas transcription uses uracil.
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The answer is jointed legs.
Arthropods has another smaller classification, which includes insects, arachnids, crustaceans and myriapods. Some of their common characteristics includes segmented body, jointed legs etc.
Others like hard shells or gills are only present in certain types of Arthropods, which in this case is crustaceans.
Meanwhile Arthropods has exoskeleton, instead of endoskeleton. It's like a hard shell outside of their body, to protect them.