Final answer:
Arrow worm eggs don't fully mature until there is sperm present. This statement is true because fertilization triggers the full maturation process of the eggs.
Step-by-step explanation:
The statement that arrow worm eggs don't fully mature until there is sperm present is True. In some species, including arrow worms, fertilization triggers the full maturation process of the eggs. The presence of sperm activates the development of the eggs, leading to their full maturity. Once the eggs are mature, they can be fertilized and develop into offspring.