Which of the following is false about the frog?

I. Eyes are bulged out and covered by a nictitating membrane that protects them while in water

II. On either side of the eyes a membranous tympanum (ear) receives sound signals

Ill. The forelimbs and hind limbs help in swimming, walking, leaping and burrowing

IV. The hind limbs end in five digits and they are larger and muscular than fore limbs that end in four digits

V. Feet have webbed digits that help in swimming

VI. Frogs exhibit sexual dimorphism