Context: This passage describes the ground spot color trait in watermelon plants:
Watermelon plants grow with their fruit resting on the ground. Over time, the bottom of each fruit develops a white or yellow spot called a ground spot. In some types of watermelon plants, the color of the ground spot is an inherited trait.
In a group of watermelon plants, some individuals have a yellow ground spot and others have a white ground spot. In this group, the gene for the ground spot color trait has two alleles. The allele for a yellow ground spot (G) is dominant over the allele for a white ground spot (g).
This Punnett square shows a cross between two watermelon plants.
What is the probability that a watermelon plant produced by this cross will be heterozygous for the ground spot color gene?
A. 1/4
B. 3/4
C. 0/4
D. 2/4
E. 4/4
Choose the right answer from the options and respond with its letter.

D