Task: Question Answering
Input (English): Question: Regarding the stability of the drugs of a proteinaceous nature of biotechnological drugs, we can say: 
 Options:  <1> Which is strongly dependent on pH. <2> That is little affected by ionic strength. <3> That being generally so high does not usually give problems in the formulation. <4> That its maximum value occurs at the pH value of lower solubility. <5> That has a slight dependence on the temperature.
Output (English): 1