Why cross pollination is better than self pollination?
Defend against diseases
Variation in species
New traits to the plant
All of the above
Because it results in species diversity, cross-pollination is preferred. No mutations result from self-pollination. Variation gives the plant new qualities that can be beneficial to it. For instance, it aids the developing plant's immunity against disease. Hence option 4 is the correct answer.
Explanation for the incorrect options :
Option 1 is incorrect because cross-pollination is the exchange of pollen grains between plants that have distinct genetic make-ups. Cross-pollination results in the generation of genetically varied progeny that are better able to fend off pests and illnesses.
Option 2 is incorrect because of species variety: When two distinct individuals' genetic material is combined through cross-pollination, more variance is present in the progeny than when the process occurs naturally. As a result of this variety, new characteristics or trait combinations may emerge that may be more suited to adapt to shifting environmental conditions.
Option 3 is incorrect because the plant acquires new qualities: Cross-pollinated plants are more likely to generate offspring with favorable features than self-pollinated plants. By choosing and crossing plants with desired qualities, new types of crops may be generated, making cross-pollination a crucial technique in plant breeding programs.