Question

Which of the following features helps birds to fly?

• A. Hollow bones
• B. Modification of forelimbs into wings
• C. Strong shoulder bones
• D. All of these

Answer 1

The correct option is D All of these

The birds can fly because their bodies are well suited for flying. Their bones are hollow and light. The bones of the hind limbs are typical for walking and perching. The bony parts of the forelimbs are modified as wings. The shoulder bones are strong. The breastbones are modified to hold muscles of flight which are used to move the wings up and down.
Hence, the correct option is D.