Which of the following statements is/are correct with regard to Nitrolim? I. It is prepared by heating calcium carbide with nitrogen. II. It decomposes into ammonia in soil. III. It is an NPK fertilizer. IV. It is an organic fertilizer. Select the answer using the code given below.

Nitrolim is the commercial name for calcium cyanamide (CaCN2), prepared by passing nitrogen gas over heated calcium carbide: CaC2 + N2 → CaCN2 + C. In moist soil it slowly hydrolyses, eventually releasing ammonia which is then nitrified for plant uptake. So statements I and II are correct. Nitrolim is a nitrogenous fertilizer only (no phosphorus or potassium), so it is not an NPK fertilizer (III is wrong). It is an inorganic synthetic fertilizer, not organic (IV is wrong). Hence only I and II are correct.