Answer:
False, they can have recessive phenotype
Step-by-step explanation:
A phenotype is a viable characteristic an individual presents as a consequence of the interaction between its environment and its genotype.
This doesn’t necessarily means that the individual’s aleles are both dominant (homozygotes), they could have one dominant and one recessive gen (heterozygotes), meaning that, if the another parent is homozygote with both recessive aleles the offspring could heritage homozygote recessive aleles that will result in a recessive phenotype.
You can observe in the image I added a punnet square that exemplifies the scenario. You can see that the offspring has 1/2 probability to have recessive phenotype.
I hope you find this information useful and interesting! Good luck!