While completing an experiment similar to the chemical experiment performed by Miller and Urey, a scientist observed that complex organic molecules were formed when precursors were heated and charged with electricity. Which of the following can the scientist conclude?

(A) The Miller-Urey experiment was inaccurate.
(B) The addition of heat allowed the precursors to form more complex organic molecules.
(C) The addition of electricity allowed the precursors to form more complex organic molecules.
(D) The experiment requires a control group without heat or electricity to make a conclusion.