A monoacid organic base (0.0915 g) requires 15 ${\mathrm{cm}}^3$ of N/20 HCl for complete neutralization. The molar mass of

A monoacid organic base (0.0915 g) requires 15 ${\mathrm{cm}}^3$ of N/20 HCl for complete neutralization. The molar mass of $122 \mathrm{g} {\mathrm{mol}}^{-1}$

Weight of the organic base/equivalent mass = normality* Volume: milliequivalence of base = milliequivalence of acid

in this case, molar mass = equivalent mass ( as it is monoacid base)
Assuming M is the molar mass, the values 0.0915/M = 1/20* 15/1000 M and 122 g/mol are suitable substitutes.

Hence, option B is correct.