The right option is; an acid
A substance that yields an anion plus a hydrogen ion is an acid.
An acid is a chemical substance often a liquid that gives a hydrogen ion (H+). Acids may either be strong or weak. Acids usually have a lower pH, and a sour taste. They react with bases and some metals such as calcium to produce salt. Acids turn blue litmus paper to red. Examples of acids are acetic acid, and hydrochloric acid.