Answer:
Woodpeckers, brown creepers and nuthatches.
Step-by-step explanation:
The birds which have two toes pointing upwards and two downwards, are known as climbing birds and they include woodpeckers, brown creepers and nuthatches.
These climbing birds are able to grip unto the bark of trees due to their claws. They usually grip on the trees while hunting for insects to capture and eat.
Additionally, climbing birds have a slender beak that is either straight or curved inward.