Diabetes, together with its serious complications, ranks as the nation's third leading cause of death, surpassed only by heart disease and cancer

(a) ranks as the nation's third leading cause of death, surpassed only
(b) rank as the nation's third leading cause of death, only surpassed
(c) has the rank of the nation's third leading cause of death, only surpassed
(d) are the nation's third leading causes of death, surpassed only
(e) have been ranked as the nation's third leading causes of death, only surpassed


Isn't "Diabetes" the subject and "ranks" is the verb? Diabetes is plural therefore "rank" should be without the s because it needs to be plural also. Please explain?