There is no correct answer to this question. The correct answer is both 1. and 2. The rotting of jute is both a microbiotic process and a chemical process.
The main constituent of jute is cellulose. Cellulose is a polymer with the formula
Cellulose reacts with water to form glucose molecules.
Both acids and enzymes like cellulase catalyze the reaction.
Microbiota like bacteria and fungi can decompose cellulose, so the process is microbiotic. They use enzymes as catalysts to carry out the process.
Whether the process is acid- or enzyme-catalyzed, it is a chemical process. One compound, cellulose, is converted to another compound, glucose, with different properties.
A microbiotic process is a subset of all chemical processes.