The disability retirement pension for local miscellaneous service subject to this article shall be one of the following:
(a)
Ninety percent of the factor applicable at age 65 as set forth in Section 21094 times final compensation multiplied by the number of years of service credited to him or her.
(b)
If the disability retirement allowance computed under subdivision (a) does not exceed one-third of his or her final compensation, 90 percent
of the benefit that would be payable to the member had the member continued in employment until age 65 but in that case the retirement allowance shall not exceed one-third of the final compensation. This subdivision is not applicable to members who are not entitled, at the time of retirement, to be credited with at least 10 years of service.
(c)
If the disability retirement allowance is derived from this section and Section 21423, and would otherwise exceed the maximums provided by these sections, the pension payable with respect to each section shall be reduced in the same proportion as the allowance computed as though there was no limit, so that the total of the pensions shall equal the maximum allowed.