in C. Write a function called pop(), which accepts a pointer to a Stack (which contains a pointer to the top of the stack). The function must remove the nodes at the top of a stack of characters. The function must also return a copy of the data found at the top of the stack. Precondition: stack must not be empty. The Node and Stack structures are defined below:

typedef struct node { char data; struct node *pNext; } Node; typedef struct stack { Node *pTop; } Stack; Be sure to write out the function header!