(B) the disability is at least 30 percent under the standard schedule of rating disabilities in use by the Department of Veterans Affairs at the time of the determination; and either
(i) the disability was not noted at the time of the members entrance on active duty (unless clear and unmistakable evidence demonstrates that the disability existed before the members entrance on active duty and was not aggravated by active military service);
(ii) the disability is the proximate result of performing active duty;
(iii) the disability was incurred in line of duty in time of war or national emergency; or
(iv) the disability was incurred in line of duty after September 14, 1978.