The correct choice is (c) Osmotic shock
Best explanation: Osmotic shock is a technique which utilizes the hypertonic and hypotonic condition for cell lysis. In hypertonic condition, water molecules move out due to osmosis and shrink the cell. Whereas in the hypotonic condition, the water molecules enter the cell, bulging the cytosol and finally bursting of cell to remove the cell content outside. 1.4 % buffered sucrose is used for this purpose. Ultrasonification and homogenization are methods to extract enzymes by physical methods. EDTA acts as a chelating agent and thus extract enzymes by chemical methods.