The correct option is (a).
Explanation
Pollination is the mechanism of transferring pollen grains from the male anther to the female stigma. Cross-pollination, also known as xenogamy or allogamy, involves the transfer of pollen to a flower on a genetically different plant of the same species.Statement-wise Analysis:
- Statement 1 is Correct: Cross-pollination is defined by the transfer of pollen grains from the anther of one flower to the stigma of a flower located on a different plant of the same kind (species). This distinction separates it from self-pollination (autogamy) and geitonogamy (transfer between flowers on the same plant).
- Statement 2 is Incorrect: Because the pollen must travel between physically separate plants, cross-pollination requires external agents for transport. These agents can be abiotic (wind, water) or biotic (insects, birds, bats). It cannot occur exclusively without the aid of such agents.
- Statement 3 is Incorrect: Cross-pollination involves the fusion of gametes from two genetically distinct parents. This process introduces genetic recombination and variation in the progeny. Offspring that are genetically identical to a single parent are characteristic of asexual reproduction (cloning), not cross-pollination.
Key Takeaway: Cross-pollination facilitates genetic diversity by combining genetic material from two different plants and relies on external pollinating agents such as wind, water, or animals for pollen transfer.