Which one of these in not a principle of cell theory

The correct answer is D) Only cells containing mitochondria can reproduce.

Explanation:

Cell theory mainly states that every organism present on this earth are made up of cell and the cell is the basic and smallest unit from which life is made up of. It also states that all the new cell that comes into existence are evolved from the old(pre-existing) cells.

Therefore any cell that contain or do not contain mitochondria can reproduce because new cells come from an old cell not from mitochondria, for example, a bacterial cell does not have mitochondria but they reproduce by binary fission.  

Therefore any cell which is living can reproduce so the principle which is not currently understood is D) Only cells containing mitochondria can reproduce.

both adhesion and cohesion are attractions.

they are different in that adhesion is the force of attraction between the molecules of two different substances, whereas cohesion is the force of attraction between molecules of the same substance.

possible examples include capillary action, in which the adhesion between water and glass causes the water to rise in a narrow tube against the force of gravity.

because of hydrogen bonding, water is extremely cohesive.

this causes molecules on the surface of water to be drawn inward, which is why drops of water form beads on smooth surfaces.

hope this .