Which part of the DNA strand is responsible for determining an organism's traits?​

Ialready know the answers to these questions and they are on the attachment. but i just need to know why that answer is the correct one. plz asap! this is for a report that i need to email by 10!

The color of the fur is the genotypephenotype.the genetic combination of alleles that determine the fur color is called the genotypephenotype.

We all have different forms of genes from our parent(s).what are these different forms called? a.alleles b.characters c.dna d.resources