Which of the following characteristics differentiates an autotroph from a heterotroph? question options: a heterotroph must obtain its energy from an autotroph or other heterotroph. autotrophs only obtain their energy from the sun. an autotroph can only obtain its energy from a heterotroph. an autotroph must obtain its energy from a heterotroph or other autotroph.. heterotrophs only obtain their energy from the sun. a heterotroph can only obtain its energy from an autotroph.