To correctly complete the sentence "Frogs_________," we need to identify the specific sound that frogs are known to make. Understanding common animal vocalizations is key here.

Frogs' Distinct Sound: The Croak

Frogs are amphibians recognized for their characteristic vocalizations, especially during breeding seasons. The sound they produce is widely known as a 'croak'.

• Croak: This term accurately describes the deep, hoarse, or throaty sound made by frogs and toads. Male frogs often croak loudly to attract mates, and the sound can vary in intensity and pattern depending on the species and environmental conditions.

Analyzing Other Vocalizations

Let's examine why the other provided options are not suitable for describing the sound made by frogs:

• Roar: A 'roar' is a powerful, deep, and prolonged vocalization typically associated with large carnivorous animals such as lions, tigers, and bears. Frogs do not produce a roaring sound.
• Hiss: A 'hiss' is a sharp, sibilant sound, often produced by animals like snakes, cats, or geese, usually as a sign of warning, fear, or aggression. Frogs do not hiss.
• Patter: The word 'patter' refers to a rapid succession of light, tapping sounds, such as the 'patter of raindrops' on a window or the 'patter of feet' on a floor. It describes a type of sound or movement, not a vocalization made by an animal like a frog.

Conclusion on Frogs' Sound

Based on the typical sounds associated with different animals, 'croak' is the precise and correct term for the sound that frogs make. Therefore, the completed sentence "Frogs croak" is the accurate choice.