Bacteria and humans are similar in that they

grow and reproduce.
produce energy.
are multicellular.
are unicellular.

Bacteria and humans are similar in that they grow and reproduce and produce energy. However, bacteria are typically unicellular organisms, while humans are multicellular organisms.

which one?

Bacteria are unicellular organisms, meaning they are made up of a single cell. Humans, on the other hand, are multicellular organisms, made up of many cells working together to form tissues and organs.