This section applies only to members of: the Employees’ Pension System; the Local Fire and Police System; the Law Enforcement Officers’ Pension System; and the Teachers’ Pension System. Except as provided in subsections (c), (d), and (e) of this section, an ordinary disability retirement allowance equals: if the member is at least normal retirement age, a normal service retirement allowance; or if the member is under normal retirement age, a normal service retirement allowance that is computed by using: the number of years of creditable service the member would have received if the member continued employment until normal retirement age; and an average final compensation the member would have received if the member continued employment without a change in earnable compensation. A member of the Employees’ Pension System or the Teachers’ Pension System who has transferred from the Employees’ Retirement System or the Teachers’ Retirement System shall receive the benefits provided under the State system from which the member transferred, offset by any refunded contributions including any interest received in connection with the transfer, if: the member applies for the retirement allowance within 2 years after the transfer; and the Board of Trustees grants a disability retirement allowance to the member. This subsection applies only to: a member of the Local Fire and Police Pension System who has transferred from the Employees’ Retirement System; or a member of the Law Enforcement Officers’ Pension System who has transferred from the Employees’ Retirement System after electing to receive benefits in accordance with Selection A (Additional member contributions) as defined in § 22-101(b) of this article or Selection B (Limited cost-of-living adjustment) as defined in § 22-101(c) of this article. An ordinary disability retirement allowance equals the greater of: a normal service retirement allowance; or 25% of the member’s average final compensation. This subsection applies only to a member of the Employees’ Pension System who: is promoted within the Department of Corrections to a position that no longer is eligible for membership in the Correctional Officers’ Retirement System as provided in § 25-201 of this article; elects not to transfer the years of creditable service the individual accrued in the Correctional Officers’ Retirement System to the Employees’ Pension System; and is eligible to receive a vested allowance from the Correctional Officers’ Retirement System. An ordinary disability retirement allowance equals: a normal service retirement allowance in the Correctional Officers’ Retirement System based on the member’s total years of creditable service accrued in the Correctional Officers’ Retirement System; plus an ordinary disability retirement allowance based on the member’s total years of creditable service accrued in the Employees’ Pension System.