Complex sentence: So for adequate low frequency response the capacitors used must be high enough, such that the reactance of each is at least ten times the input impedance of each stage, at the lowest frequency of interest.
Split into simpler sentences: So for adequate low frequency response the capacitors used must have high capacitance ratings. They should be high enough that the reactance of each is at least ten times the input impedance of each stage, at the lowest frequency of interest.