[单选题]
The electron micrograph below5xm8eok vr -uf/ ,lf5i showz41byv/q)5ev goecy (gaym kxz/+2 p:s a cell of the bacterium Vibrio cholerae. Which of the labelled structures main x b2e kv e +q5p/ygc/ga(yv:4)zoz1ymtains the cell’s shape and protects the cell from lysing during osmosis?