Calculate the net irrigation requirement of maize crop
Effective root zone = 5 cm, B.D. = 2.15 g/cc, FC = 28%, PWP = 11%

Correct option is A

Available soil moisture = FC − PWP = 28 − 11 = 17%.
Net irrigation requirement = (ASM/100) × BD × depth.
= (17/100) × 2.15 × 5.
= 1.83 cm approximately.
Rounded value is 1.8 cm.
Hence option (a) is correct.