Step 1: Recall the structure of the ovary.
Inside the ovary, ovules are borne on a tissue known as the placenta.
This is where the ovule is attached and from where the funicle arises.
Step 2: Eliminate other options.
- Synergids: Located near the egg apparatus inside the embryo sac.
- Embryo sac: Female gametophyte, not the attachment point.
- Tube cells: Part of the pollen grain, not the ovule.
Step 3: Conclusion.
Hence, ovules are attached to the ovary by the placenta.