Two parents with normal phenotypes have a daughter who genetically inherited a disorder. Explain how this is possible.

This is possible only if the two parents ar e heterozygous for the trait and the genetic disorder is inherited in a recessive fashion.

Explanation: Phenotype is the outward appearance of an organism. Genotype is the genetic makeup of an individual, a genotype can not be seen but it is manifested in an observable trait known as phenotype. Every trait is controlled by a pair of gene inherited one from each parent. When the two parents are heterozygous for the trait (having one dominant allele and one recessive allele for the trait), a child can inherit two recessive alleles one from each parent.

For example, when two parents are heterozygous for sickle cell disease AS, a cross between them will produce an offspring with sickle cell disease. As x As =AA, As, As, and ss. (A is dominant and s is recessive).

the answer to your question is b

the correct answer is 2 and 4