Answer:
The last option
Step-by-step explanation:
Since the ability to roll the tongue is a dominant trait, the percent chance that all children will be tongue rollers depends on the tongue rolling ability of the parents
If both parents are homozygous dominos for the trait, there is a 100% chance that their children will be tongue rollers.
If both are heterozygous for the trait, there is a 75% chance of production tongue rollers