OG10-SC-101 dispute or amount

101. Even though the direct costs of malpractice disputes amounts to a sum lower than one percent of the $541 billion the nation spent on health care last year, doctors say fear of lawsuits plays a major role in health-care inflation.
                

(A)  amounts to a sum lower
                

(B)  amounts to less
                

(C)  amounted to less
                

(D)  amounted to lower

(E) amounted to a lower sum

请问动词是哪个？if the verb is "amount", so what is "dispute"?

谓语动词使amount，dispute 是名词

Right, amount here is usded as a verb, means add up in number or quantity;  "The bills amounted to $2,000", amount=add up=come,"The bill came to $2,000" .

In general, amount to = add up to = come to.

The whole sentence can be compressed to
Even though the...costs of (malpractice) disputes amounted to ...one percent of...,doctor says...