I was so excited to see the Jacuzzi size bathtub because I do n't have a bathtub at my house . Since it was about 40 degrees ( Remember that Mark Twain quote about the " coldest winter I ever spent was a summer in San Francisco " ? Turns out , it 's true .

Select from the following. [I] They live in a cold environment . [II] Mark Twain recommended one . [III] They live in a hot environment . [IV] They wanted to emulate Mark Twain 's house .
Answer the following question: Why did the narrator opt for a Jacuzzi at their house ?
[I]