Nerve cells specialize in carrying messages. Which organism has nerve cells?

A. horse

B. amoeba

C. bacterium

D. paramecium

Nerve cells or neurons are, fundamentally, cells of the nervous system, they are responsible for the transmission of nerve impulses and communicate with one another through connections called synapses.

Neurons are typical of all vertebrates, although in the rest of the animal kingdom there are other cells that have similar functions.

So, the right answer is A. Horse.

Nerve cells are a physiological feature that evolved for multicellular organisms therefore from the above only a horse would have nerve cells.