A Long Piece of Ribbon Wired Along Both Long Edges

A long piece of ribbon wired along both long edges is twisted into a helix and wrapped around individual pipe cleaners that have been rolled into spools; this grouping is then twisted (super coiled) again to condense it.This could be best used as a simple model for a

A) plasma membrane, where the pipe cleaners represent the phospholipid bilayer and the ribbon represents proteins embedded in the membrane.
B) cell wall.
C) mitochondrion.
D) chromosome, where the pipe cleaners represent bundles of proteins around which the DNA double helix (wired ribbon) is wrapped.