context: A white duck is spreading its wings while sitting on the water.
hypothesis: It is impossible that the duck spread its wings to fly when it heard a gunshot.
valid_hypothesis: It is impossible that the duck spread its wings to fly when it heard a gunshot.
invalid_hypothesis: It is certain that the duck spread its wings to fly when it heard a gunshot.
hypothesis_assertion: The duck spread its wings to fly when it heard a gunshot.