Match the Column I with Column II .

A - 2,B - 3,C - 4,D - 1

The correct answer is Option (2) - A - 2,B - 3,C - 4,D - 1

A. Viability of pollen grains: The viability of pollen grains refers to their ability to germinate and fertilize the ovules. It is influenced by factors such as prevailing temperature and humidity. Suitable temperature and humidity conditions are necessary for pollen grains to remain viable and successfully complete fertilization.

B. Autogamy : In this type, pollination is achieved within the same flower. Transfer of pollen grains from the anther to the stigma of the same flower . So flower and plant should be bisexual .Autogamy in such flowers requires synchrony in pollen release and stigma receptivity .

C. Pollen allergy: Pollen grains of many species cause severe allergies and bronchial afflictions in some people often leading to chronic respiratory disorders– asthma, bronchitis, etc. It may be mentioned that Parthenium or carrot grass that came into India as a contaminant with imported wheat, has become ubiquitous in occurrence and causes pollen allergy.

D. Xenogamy – Transfer of pollen grains from anther to the stigma of a different plant  means in between unisexual plants . This is the only type of pollination which during pollination brings genetically different types of pollen grains to the stigma.

So, the correct pairing of Column I and Column II is: A - 2, B - 3, C - 4, D - 1