This graph is indicating a fixed exchange rate that prevents the foreign exchange rate from moving outside of the upper and lower limits.
Answer: Option D.
Step-by-step explanation:
A fixed exchange rate, now and again called a pegged exchange rate, is a kind of swapping scale system in which a cash's worth is fixed or pegged by a money related authority against the estimation of another money, a container of different monetary forms, or another proportion of significant worth, for example, gold.
In this case, the exchange rate is fixed because the limits are fixed in this case.