Liquid-liquid extraction is best suited to separate a mixture of compounds when:
A. The mixture contains compounds with similar polarities but different solubilities.
B. The mixture contains compounds with similar solubilities but different molecular weights.
C. The mixture contains compounds with similar melting points but different polarities.
D. The mixture contains compounds with similar molecular weight but different polarities.
E. The mixture contains compounds with similar molecular weight but different melting points.