Bees, which are known for aiding in pollination, with which process?

Bees help to transfer pollen grains from anther to pistil of flower.

Explanation:

Pollination is the process of transferring pollen grain from anther of male to stigma or pistil of flower.

Bees are good pollinators. Bees feed on nectar and collect pollen grains from anther. Some of the pollen grains stick to the hair of the mouth, on visiting another plants, they rubb this pollen grain on stigma or tip of pistil(female reproductive organ) of flower.