Read the following context and choose the best option to answer the question.
Context: We could use the buddy system so as to safely navigate Cambridge . It was a brilliant , perfect , flawless plan . And Mom , though she never admitted it , was VERY OBVIOUSLY impressed , and oh - so - graciously allowed me to sleep over Liam 's so I could head down with Fred and Liam in the morning . And that 's what we did ! ... A lot happened . Cat screamed at geese . Cat had too much coffee . Cat picked on Liam .
Question: What may be the reason their mother allowed them to stay over at their friend 's house ?
Options: 
- Because she trusted them .
 - Because she did n't want them to be separated .
 - Because she wanted them to have a good time .
 - None of the above choices .


Because she trusted them .