the outermost layer of the cell envelope of a gram - positive cell is the \n\nperiplasmic space\npeptidoglyca…

Brief Explanations:

Gram - positive cells have a thick peptidoglycan layer as their outermost cell - envelope component. They lack an outer membrane. The periplasmic space is between the inner and outer membranes in gram - negative cells, and the cytoplasmic membrane is internal to the peptidoglycan layer in gram - positive cells.

Answer:

B. peptidoglycan layer