Concept:The animal foot shown is a webbed foot, an adaptation that assists in moving through water.
Explanation:In this type of foot, the toes are joined by thin layers of skin called webs.
These webs increase the surface area of the foot significantly.
When the animal pushes its foot backwards through water, the webbed surface pushes a large volume of water in the opposite direction.
According to Newton's third law of motion, this backward push of water produces an equal and forward reaction force on the animal.
Thus, the webbed foot works like a paddle, propelling the animal smoothly and efficiently in water.
This adaptation is commonly seen in aquatic birds and other water-living animals.
It is not used as bait, for scratching soil, or for killing prey.
Answer:B. used as a paddle for swimming.
