United Nations International Years related to agriculture:

• 2010 was observed as the International Year of Biodiversity.
• 2012 was designated as the International Year of Cooperatives.
• 2016 was declared as the International Year of Pulses (IYP) by the United Nations General Assembly under the leadership of FAO to heighten public awareness of the nutritional and environmental benefits of pulses.
• 2019 was observed as the International Year of Indigenous Languages.

Aroma chemistry of basmati and scented rice cultivars:

• Monosilicic acid is an inorganic silicon species taken up by plant roots for mechanical rigidity.
• Monoacetyl-1-pyrroline is a non-standard name variant.
• acetyl-1-pyrroline (2-AP) is the primary volatile compound responsible for the characteristic pleasant aroma in scented rice varieties like Basmati and Jasmine.
• Disilicic acid is a polymerized silicon molecule unrelated to grain aroma.

Classification of sub-cellular biological agents:

• virion is an intact, fully assembled, infectious viral particle outside the host cell.
• Viroids are small, circular single-stranded infectious RNA molecules devoid of protein coats that infect plants.
• Bacteriophages (or simply phages) are specialized viruses that infect, replicate within, and lyse (kill) bacterial cells.
• Antibodies are protective immunoglobulins produced by the animal immune system in response to antigens.

Nutritional definitions and dietary standards:

• RDA officially stands for Recommended Dietary Allowances, defined by ICMR-NIN and international nutrition bodies as the average daily dietary nutrient intake level sufficient to meet the nutrient requirements of nearly all healthy individuals in a particular life stage and gender group.
• 'Daily' is frequently used colloquially but 'Dietary' is the formal scientific terminology standardized by ICMR and WHO.
• 'Required' is incorrect because the standard provides recommended allowances incorporating safety margins.
• 'Required Daily Allowance' is incorrect.

Option analysis:
(A) Pusa Basmati 1728 is a bacterial blight resistant version of Pusa Basmati 6 (incorporating xa13 and Xa21). The bacterial blight resistant version of Pusa Basmati 1 is Pusa 1460 (Improved Pusa Basmati 1).