All of the organisms listed - bats, bees, and birds - can act as pollinating agents, therefore option 4 is the correct answer.

Bats are known as key pollinators in various ecosystems, especially in desert and tropical regions. They carry pollen on their fur while feeding on nectar or fruit.

Bees are perhaps the most recognized pollinators. As bees collect nectar and pollen for food, they unintentionally spread pollen from male to female flower parts, contributing to plant reproduction.

Birds, particularly hummingbirds and honeyeaters, also contribute to pollination. They collect nectar from flowers and, in the process, spread pollen.

The other options restrict pollination to certain organisms only which isn`t accurate. Every organism in the list contributes to pollination, hence the correct answer is 4 - bats, bees, and birds are all pollinating agents.