Which of the following vegetable crops is cross-pollinated due to protandry?

Correct option is A

Protandry refers to the condition where the male parts (anthers) of the flower mature and shed pollen before the female parts (stigma) become receptive. This promotes cross-pollination because when a flower's own stigma is ready, its own pollen is already gone.
Key Points:
· Onion (Allium cepa):
· Exhibits protandry.
· The anthers dehisce (release pollen) before the stigma becomes receptive.
· This temporal separation encourages cross-pollination between different plants.
· Pollinators, especially bees, play a major role in transferring pollen from one flower to another in onions.
· Therefore, onions are classified as highly cross-pollinated crops.
Other Options Explained:
· (b) Radish:
· Radish exhibits self-incompatibility, not mainly protandry.
· (c) Cabbage:
· Cross-pollination mainly due to self-incompatibility, not protandry.
· (d) Cauliflower:
· Also relies on self-incompatibility for cross-pollination rather than protandry.