The process that produces a similar appearance among unrelated groups of organisms is a. coevolution. b. mass extinction. c. punctuated evolution. d. convergent evolution.

C. Convergent evolution.

Explanation:

Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last common ancestor of those groups.

answer; /// i believe that the correct answer is (50%);

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.