49. 給定一陣列 a[10]={ 1, 3, 9, 2, 5,8, 4, 9, 6, 7 },i.e., a[0]=1,a[1]=3, ⋯,a[8]=6, a[9]=7,以 f(a, 10) 呼叫執行右側函式後,回傳值為何?[105/01/02](A) 1(B) 2(C) 7(D) 9