Can someone help me with this test please??

R masks —or covers— r, so it only needs one copy to express its phenotype. This means it is the dominant allele.

Explanation:

In genetics, alleles are the members of an allelic pair that contain the genetic information related to a specific characteristic.

The dominant allele is one whose presence is sufficient to mask the expression of a recessive allele, so the phenotype shown is the dominant one.

A recessive allele needs to be present in both components of the allele pair in order to be expressed in the phenotype.