The statement that is true about pollination in flowers is:
Bees pollinate flowers when pollen gets stuck to their bodies, then is transferred to the stigma.
This accurately describes how bees and other pollinators can transfer pollen from the anthers of one flower to the stigma of another, facilitating pollination.
The other statements contain inaccuracies:
- Animals do not drink nectar from the base of the filaments (which are part of the flower's structure), but rather from the nectar-producing structures (nectaries).
- The stigma does not hold the ovules; ovules are held within the ovary. The stigma is where pollen lands and begins the fertilization process.
- While many plants reproduce sexually through cross-pollination, some plants can self-pollinate, meaning pollen can come from the same flower or plant.