If a qualified retirement plan provides a retirement benefit equal to 1.75% per year of service multiplied by final average salary and the plan uses the offset method of permitted disparity, which of the following statements correctly describe the application of this method? I. The plan will provide for a reduction in benefits based on a percentage of the normal Social Security retirement age benefit. II. The plan may be a defined contribution plan or a defined benefit plan. III. An offset equal to .75% of earnings below the covered compensation limit may be used to reduce a participant's plan benefit. IV. Up to 50% of the Social Security retirement benefit may be offset with this method. I and II only I and III only II and IV only I, II, and III only I, II, and IV only