C语言中为什么函数形参中二级指针和一级指针指输出的结果一样

#include <stdio.h>
void show(char **x,int n)
{
int i;
for (i=0;i<n;i++)
{
puts(x[i]);
}
}
int main()
{
char *book[]={
"《荒野的呼唤》",
"《时光之轮》",
"《老人与海》",
"《教父》",
"《基督山伯爵》",
"《地海传说》",
};
int size=sizeof(book)/sizeof(book[0]);
char **p=book;
show(p,1);
show(book,size);
return 0;
}