Question

which is a straight fertilizer​

Answer 1

$\huge\mathfrak\red{Answer \: :-}$

Simple or straight fertilisers are designed to supply only one nutrient element. Depending upon the nutrient availability they are further classified as nitrogenous, phosphatic and potassic fertilisers.

Ammonium nitrate in the form of 'Nitram', containing 34.5% of nitrogen, is a good example.