Which of the following pairs is not correctly matched in the term of Organic Substances and C/N ratio?

The carbon and nitrogen ratio of soil microorganisms is near 8 : 1. Soil microorganisms must acquire enough carbon and nitrogen from the environment in which they live to maintain that ratio in their bodies.
The C/N ratio of organic matter in soil is 10 : 1 approx.
The C/N ratio of rotted manure is quite higher and it is 20 : 1. Manures and legume straws will decompose in soil without net immobilization of N.
The recommended proportion of C/N in sawdust is 3 : 2, not 1000 : 1.
Saw dust contains 40% lignin and 60% cellulose, only 0.048% of nitrogen and traces of phosphorus, potassium and calcium.