Customary expressions using 腕（うで）, an arm

あの いしゃは うでが いい。

1. That doctor is competent.
2. That doctor has good connections (with other doctors).
3. That doctor has long arms.
4. That doctor’s arms look beautiful.

The answer is a. 腕（うで） が いい、腕（うで）が立（た）つ means “skillful”

When it is used as a contact clause, が often changes to の but the meaning is the same.

ジョンさんは 腕（うで）の立（た）つ 職人（しょくにん）だ。
= John is a skillful workman.

<Other expressions with 腕（うで）>

腕（うで）が鳴（な）る = be iching for action

腕（うで）が上（あ）がる = to acquire more skill, to improve in ability

腕（うで）が鈍（にぶ）る = to lose one’s touch

腕（うで）を振（ふ）るう = to display one’s skill

腕（うで）を競（きそ）う = to compete