The best defined function of manganese is in the splitting of water to liberate oxygen during photosynthesis. It is absorbed in the form of manganese ions (Mn²⁺). It activates many enzymes involved in photosynthesis, respiration and nitrogen metabolism.

Correct Option: A

The best defined function of manganese is in the splitting of water to liberate oxygen during photosynthesis. It is absorbed in the form of manganese ions (Mn²⁺). It activates many enzymes involved in photosynthesis, respiration and nitrogen metabolism.

Biotin, also known as vitamin H, is a water-soluble B-vitamin. It is a coenzyme for carboxylase enzymes, involved in the synthesis of fatty acids, isoleucine, valine and in gluconeogenesis. Sulphur is a constituent of biotin.

Correct Option: A

Biotin, also known as vitamin H, is a water-soluble B-vitamin. It is a coenzyme for carboxylase enzymes, involved in the synthesis of fatty acids, isoleucine, valine and in gluconeogenesis. Sulphur is a constituent of biotin.

Phosphorus, potassium, sulphur and calcium play an important role in plants growth. These minerals are required in large amount. Phosphorus is required for all phosphorylation reactions and constitution of cell membrane, nucleic acids and some proteins. Potassium is related with protein synthesis, closing and opening of stomata and activation of enzyme. Calcium regulates metabolic activities, function of cell membrane and stabilizes the structure of chromosomes. Sulphur is the main constituent of the amino acids, cystine and methionine, coenzymes and vitamins.

Correct Option: D

Phosphorus, potassium, sulphur and calcium play an important role in plants growth. These minerals are required in large amount. Phosphorus is required for all phosphorylation reactions and constitution of cell membrane, nucleic acids and some proteins. Potassium is related with protein synthesis, closing and opening of stomata and activation of enzyme. Calcium regulates metabolic activities, function of cell membrane and stabilizes the structure of chromosomes. Sulphur is the main constituent of the amino acids, cystine and methionine, coenzymes and vitamins.

Nitrogen, phosphorus, potassium, calcium, sulfur and magnesium are the macronutrients.

Correct Option: D

Nitrogen, phosphorus, potassium, calcium, sulfur and magnesium are the macronutrients.

The nitrifying bacteria bring about transformations of ammonia to nitrite and of nitrite to nitrate.

Correct Option: A

The nitrifying bacteria bring about transformations of ammonia to nitrite and of nitrite to nitrate.