Which of the following organelles contain ribosomes?

Identify the components labelled $A, B, C$ and $D$ in the diagram below from the list $(i)$ to $(viii)$ given along with:
Components:
$(i)$ Cristae of mitochondria
$(ii)$ Inner membrane of mitochondria
$(iii)$ Cytoplasm
$(iv)$ Smooth endoplasmic reticulum
$(v)$ Rough endoplasmic reticulum
$(vi)$ Mitochondrial matrix
$(vii)$ Cell vacuole
$(viii)$ Nucleus
The correct components are:

Choose the incorrect match.

Select the correct match for $X$ and $Y$:

Column $X$	Column $Y$
$(1)$ Motile bacteria	$(P)$ Slime layer
$(2)$ Glycocalyx	$(Q)$ Ribosomes
$(3)$ Gas vacuole	$(R)$ Flagellin protein
$(4)$ $20 \, nm$ diameter	$(S)$ Autotrophic bacteria

In the given figure,what do the labeled parts 'a' and 'b' represent respectively?

What is meant by the Endomembrane system? Which cell organelles are included in it? Provide brief information.