What type of fungi digests hemicellulose and cellulose?

The correct answer is brown rot fungi, as these fungi specifically break down cellulose while leaving behind lignin, the structural component of cell walls in wood. This selective degradation focuses on the polysaccharides in the wood, leading to a characteristic brown coloration as the wood decays. Brown rot fungi rely on enzymes that target the hemicellulose and cellulose, effectively digesting these components and weakening the wood material.

White rot fungi, on the other hand, have a broader decomposition capability, as they can break down both lignin and cellulose, resulting in a different decay pattern compared to brown rot fungi. Dry rot fungi, which is often used to describe a type of wood decay predominantly caused by certain species of brown rot fungi, specifically refers to the drying out of wood as it decays, but doesn't solely focus on their ability to digest hemicellulose and cellulose.

The option suggesting all types of decay fungi is too broad since not all decay fungi have the same enzymatic capabilities. Thus, brown rot fungi are specifically recognized for their unique digestion of hemicellulose and cellulose within their ecological niche.