Final answer:
Particle-board shelves are not considered organic because they are made from wood particles and resin or glue that may contain chemicals. Cotton towels, linen upholstery, and wool throw blankets can all be made from organic materials, meeting organic standards. The correct option is O particle-board shelves.
Step-by-step explanation:
The item that is NOT organic which Selma could select for the all-natural salon is particle-board shelves. Particle-board typically consists of wood particles mixed with a resin or glue, which may contain formaldehyde or other chemicals non-conducive to an organic certification. In contrast, cotton towels, linen upholstery, and wool throw blankets can all be sourced from organic materials, assuming they have been produced in accordance with organic farming and processing standards.