I met a friend of mine_________ in the street yesterday.  We didn't meet on purpose.           [ ]

A. by accident              

B. by the end          

C. by mistake              

D. in the end

已有定义如下：
struct node
int data;
struct node *next;
*p;
以下语句调用malloc函数，使指针p指向一个具有struct node类型的动态存储空间。请填空。
p=(struct node *)malloc( 【10】 );