After the following code executes, what value will be stored at offset [str2+4]?
1: .data
2: str1 byte "aaax",0
3: str2 byte 10 dup(0ffh)
4: .code
5: mov edi,0
6: l1: mov al,[str1+edi]
7: cmp al,0
8: je l2
9: mov [str2+edi],al
10: inc edi
11: jmp l1
12: l2:

a. cannot be determined
b. ascii code of "x"
c. 00h
d. 0ffh