Here's a problem to solve: The ability to roll the tongue in humans is coded by the dominant allele R. The inability to roll the tongue is coded by the recessive allele r. A man with an RR allele combination for the trait produces a zygote with a woman with an rr allele combination for the trait. Which allele combination could occur in the zygote?

Among the 4 following options, which is the correct answer?

- A: R
 
- B: rr
 
- C: Rr
 
- D: RR
 