Context: I did n't have a house key , either . I think it was winter and I was very cold . I kept walking from the backdoor to the front door hoping that one of them would miraculously become unlocked .

Question: What 's a possible reason the writer did n't have a house key ?
Options:
0. None of the above choices .
1. Because they forgot to bring it with them .
2. Because it was winter and very cold .
3. Because they kept walking from back door to front door .
Answer: 1