Answer:
D) You only want to determine the cell wall type, not any biochemical
Step-by-step explanation:
Basically selective media is used in the culture medium meant for growing only a specific microorganism, while preventing the growth of any other microbes in the medium.It is used for ensuring the growth and survival of a desired microbe with a desired characteristics, while suppressing the growth of unwanted competitor. it its primary use it to ensure the survival of needed microbes, while neutralizing or killing any unwanted microorganism.
However, in order to distinguished one organism from another in a culture medium , that is to find out if a micro organism is present or not, biochemical properties displayed by the organism when an indicator is added to the medium is usually used . That is to identify a specific microbes and therefore to differentiate from others in the media . It characterise the growth of a particular microorganism based on the biochemical properties observed when an indicator is added. it does not kill the other microbes present.
Based on this, option D is correct, because, the objective was not to identify the microorganism based on biochemical properties;or to distinguished one microbes from another;but rather to select the organism through identification of the cell structure.