Answer:
Due to feeding on the nectar of flower.
Explanation:
Some flowers look like insects or birds that are their primary pollinators because these insects or birds feeds on the liquid present in that liquid. The flower has liquid inside it which is known as nectar that is the food for many insects and birds so when these birds came to these flowers for feeding they also leads to pollination so that's why some insects and birds are the primary pollinators of some flowers.
