You are going to do a monohybrid cross between two flowers. One flower is white, the other flower is red. The red flower is homozygous. Which Punnett square accurately depicts a monohybrid cross between this white flower and this red flower? Quiz notes: Capital letters indicate dominance and lower case letters indicate recessive alleles. Alleles will be indicated by R and r. Red is the dominant flower color White is the recessive flower color

Explanation:

As given;

Here red is the dominant flower which is represented by RR and white is the homozygous recessive flower is represented by rr.

After having monohybrid cross between RR x rr we will get all the progeny having genotype Rr and phenotype of plants are Red.

      Punnett square

                                            R          R                                                  

                                    r       RrRr

                                    r       Rr  Rr

the answer to your question is b