What are two different forms of a single gene called? O factors
O chromosomes
O alleles
O traits

C, alleles

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=> O alleles

Explanation:

Allele are two different forms of a single gene.

chlorophyll a: this is the most abundant pigment in plants. chlorophyll a absorbs light with wavelengths of 430nm(blue) and 662nm(red). it reflects green light strongly so it appears green to us.

he forelimbs below belong to four species that descended in a direct line from the ancestral mammal shown above. of the four descendants shown, which species most likely appeared earliest in evolutionary history?