What might wilted lettuce to become crisp again?
a) placing it in a salt-water solution
b) soaking it in cold pure water
c) cooking it
d) chopping it up with a knife
why?

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.