pollination requires pollinators / pollinating animals & plant reproduction / seed production requires pollination ->  plant reproduction requires pollinating animals  plant reproduction requires pollinating animals & if something is required for a process then that something positively impacts that process ->  pollinating animals have a positive impact on plant reproduction  pollinating animals have a positive impact on plant reproduction & a bee is a pollinating animal ->  bees have a positive impact on plant reproduction  bees have a positive impact on plant reproduction & helping something has a positive impact on that something ->  bees help plant reproduction  a flower is a part of a plant & helping something helps the parts of that something ->  helping a plant helps that plant's flowers  bees help plant reproduction & helping a plant helps that plant's flowers -> bees help flowers by helping plant reproduction