Insects help in

$\begin{array}{1 1} (a)\;\text{to food and crops} \\ (b)\; \text{spread pollen to other plants} \\ (c)\; \text{to cure diseases} \\ (d)\; \text{reproduction of plants} \end{array}$

Bees, wasps, butterflies, moths, flies and even some beetles can carry pollen from one flower to another. For self-pollinating flowers, insects move pollen to the parts of the flower that need it. Some insects can carry pollen over long distances, which can help to spread genetic diversity in a plant population.SO they help to transfer pollen to plants.