If the demand for a product is inelastic, which of these statements must be true?

The true statement is:
The demand for a product is inelastic if the situation in which the number of goods demanded or supplied of a service or good is unchanged when the cost or price of that service or good changes. It also means that when the price increases, consumers’ buying practice, and routine stays just the same, and when the price decreases, consumers’ buying practice, and routine also remain unaltered.

The answer is a. hope this