Salt concentration typically found in alkali (sodic) soils is:

Correct option is B

Alkali/sodic soil characteristics (USDA + ICAR–CSSRI):
· ESP > 15%
· SAR > 13
· pH > 8.5
· EC usually < 4 dS/m (not primarily saline, mainly sodic).
Why other options are wrong
· (a) EC > 4 dS/m applies to saline soils, not sodic.
· (c) pH <6 = acidic soil.
· (d) EC <1 & ESP <2 = normal soil.