Final answer:
NH₄⁺ (ammonium ion) is an example of a Brønsted-Lowry acid because it can donate a proton to become NH₃ Therefore correct option is (ammonia).
Step-by-step explanation:
An example of a Brønsted-Lowry acid among the options given is NH₄⁺. A Brønsted-Lowry acid is characterized by its ability to donate a proton (H+) to a base. NH₄⁺ (ammonium ion) can donate a proton to become NH₃ (ammonia), hence acting as an acid according to the Brønsted-Lowry definition.
Other examples of Brønsted-Lowry acids include HCl, H₂SO₄, and HNO₃. All of these have ionizable protons that they can donate to bases.