A. The separation of functions ensures that photosynthesis can continue running no matter what light conditions are present.
B. The presence of separate light-dependent and light-independent reactions ensures that the plant can survive through day and night.
C. Thylakoid and stromal fractions correspond to regions in the intact chloroplast that have overlapping functions.
D. Compartmentalization within the chloroplast keeps the light-dependent and light-independent reactions in close proximity but separated.