What is true about the relationship of dna and genes?

a. each gene contains a segment of a dna molecule
b. segments of genes contain the code to make dna
c. segments of dna contain the code to make a gene
d. each dna molecule makes up a segment of a gene

i need asap

and

what determines the similarities in anatomical features among organisms

a. predator prey relationships
b. chromosomes and genes
c. location on earth
d. environmental conditions