The answer would be I and III only.
Unanticipated inflation happens when people only find out about an increase in price of goods and services, only when it has already increased.
Workers are hurt by this, especially when wage rates are fixed because their expenses for daily living will increase and the income they make might not be enough to accommodate the increase.
Lenders are affected because the money they lent will not have the same purchasing power than it originally had when they lent it.
