Which component is a protein fiber of the extracellular matrix?

Protein  collagen

Explanation:

Protein  collagen is made up of a matrix of carbohydrate and proteins which comprises protein collagen as a major component of extracellular matrix. Protein collagen assembles itself into long fibrils known as collagen fibril which is very essential for providing strength and structural integrity to the tissue. Collagen fibers are woven with proteoglycans which is further connected to the long polysaccharide backbone. The matrix also comprises of some protein connectors such as integrins, fibronectin molecules etc. which establish connection among themselves or the other elements of the matrix

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products

the answer would be   10%