Correct option is B
Base Saturation formula:
· Indicates
soil fertility and pH status.
· High BS → more fertile soil; low → acidic soil.
· Found in
Brady & Weil Soil Science.
Why other options are wrong
· (a) Inverse of correct.
· (c) Exchangeable acids not used for BS; used for AEC.
· (d) ESP only measures Na saturation, not BS.