Pam and Billy saw some eggs in the nest in their apple tree. They wondered about the baby birds inside the eggs. "Let's watch them!" said Billy. "We can count the days until they hatch." "This is like a science experiment in school," said Pam. The two children marked the calendar until the eggs hatched. What would be a good testable question for their research? A) How do birds hatch from their eggs? B) What do baby birds eat while they are inside their eggs? C) How long will it take for the baby birds to hatch from the eggs? D) The baby birds will hatch three weeks after they have been laid in the nest.