The correct answer is It is a salt of a strong acid and a weak base.Concept:pH scale:A scale developed to measure the concentration of hydrogen ions in a solution is known as the pH scale where p in pH implies potenz in German.pH scale ranges from 0 (highly acidic) to 14 (highly alkaline).The pH of a neutral solution is 7.The basic strength increases as we move from 7 to 14 on the pH scale.Acid:It is sour in taste.It turns the blue litmus color into red.It has a pH value of less than 7. It is represented by a value less than 7 on the pH scale.Base:It is bitter in taste and slippery to touch.It turns the red litmus color into the blue.It is represented by a value greater than 7 on the pH scale.Explanation:Acid and base react together to form salt and water. Weak acid + strong baseBasic saltStrong acid + weak baseAcidic saltStrong acid + strong base Neutral saltWeak acid + weak base Neutral saltThe salt formed has a pH value of 4.5. So, it is acidic in nature. Thus, it is formed by the reaction between a strong acid and a weak base.