Answer:
The correct answer would be B. Hundreds of pollen grains pollinated the ovules.
Seed is the ultimate result of sexual reproduction in plants.
The male part, that is, stamen produces male gametes termed as pollen grains.
The pollen grains fall on the female part, that is, stigma and reach ovary through pollen tube.
In the ovary, fertilization takes place after which ovary develops into the fruit and ovule develops into the seed.
Thus, if oranges have hundreds of seeds that means, hundred of pollen grains pollinated the ovule.