Final answer:
The ovum is larger than the sperm in Drosophila bifurca species.
Step-by-step explanation:
In the Drosophila bifurca species, the ovum is larger than the sperm.
According to the information provided, the egg contributes all the cytoplasm and organelles to the zygote, while the sperm only contributes one set of chromosomes. The egg is much larger than the sperm because it contains almost all of the cytoplasm and necessary materials for the developing embryo.