Which of the Following Was the Result on Appeal in King

Which of the following was the result on appeal in King v. American Family Mutual Insurance Company; American Standard Insurance Company of Wisconsin, the case in the text involving whether for an injury occurring outside the state, personal jurisdiction in Montana could be asserted over the defending insurers who had appointed an agent for service of process there but had done no business in the state?

A) That appointment of an agent for service of process does, standing alone, subject foreign corporations to jurisdiction in Montana for acts performed outside of Montana.
B) That Montana law regarding appointment of an agent for service of process does not, standing alone, subject foreign corporations to jurisdiction in Montana for acts performed outside of Montana, at least when the corporations transact no business in the state.
C) That regardless of whether an agent for service of process had been appointed, as a matter of law, insurers may be sued in any state in the U.S.
D) That regardless of whether an agent for service of process had been appointed, as a matter of law, an insurer may only be sued in its state of incorporation.
E) That regardless of whether an agent for service of process had been appointed, as a matter of law, an insurer may only be sued in the state in which its principal place of business is located.