Biotechnology is being used to address problems in all areas of agricultural production and processing. This includes plant breeding to raise and stabilize yields; to improve resistance to pests, diseases and abiotic stresses such as drought and cold; and to enhance the nutritional content of foods. 

Genetic modification by the introduction of the recombinant DNA has resulted in the creation of tailor-made plants that can be pest resistant, drought resistant, herbicide resistant, etc. It has supplied alternative to dairy farm industries by modifying plants and animals. It has also resulted in the creation of biofortified crops that have enhanced nutritional values of food.

Hybridisation is the interbreeding between two genetically different organisms from the same or different species. When such interbreeding is between different species it is known as interspecific hybridisation. Genetically modified crops are those that are genetically engineered by introducing the genes of the desired trait (character) into the plants. When the cross is between two different varieties of the same species then it is known as intervarietal hybridisation. So, the correct options are 'Hybridisation means crossing between genetically dissimilar plants and Introducing genes of the desired character into a plant gives genetically modified crop'.

Answer is option A i.e. "1,00,000"
India was home to more than 1,00,000 rice varieties, which displayed diversity in taste, nutrition, pest-resistance and adaptability to a range of conditions.

Agrochemical based agriculture is used to increase the food production. It includes use of agrochemicals such as fertilisers and pesticides.

• The Nobel Laureate, Norman E. Borlaug at International Centre for Wheat and Maize Improvement in Mexico , developed semi-dwarf varieties of wheat. Example; Sonalika and Kalyan Sona which are high yielding and disease resistant.
  
• Herbert Boyer is a researcher in biotechnology and discovered the restriction enzymes. 
  
• William Harvey is the father of circulatory system. 
  
• Maer Mallon known as Typhoid Mary . She was the first carrier of the pathogen associated with typhoid fever.

Osmotic pressure is the pressure required to stop the flow of pure water or solvent into a solution across a partially permeable membrane. Water moves from a region of low osmotic pressure to a region of high osmotic pressure. As high leaves of NaCl is accumulated in the cells, of modified plant the osmotic pressure of cytosol is increased. Accumulation of salts in vacuoles causes compartmentalization of salts away from the cytosol and protects cytosol from the harmful effects of the high salt concentration. 

Foliar spray generally contains the micronutrients of Mn because there exist strong cuticular affinity for the manganese.

Complete destruction of the potato crop by late blight caused the 'Irish potato famine' in the middle of the 19th century, led to the search for resistant plants. Single genes for resistance to late blight (R genes) were discovered nearly 100 years ago in S. demissum, a wild potato species indigenous to Mexico.

Biotechnology is the area involving the development of living organisms by so technical applications. It uses biological systems to modify the products. It is largely used in agriculture for developing genetic engineering and new crops yields.