I. 閱讀測驗         A small group of people scattered throughout the world have made the choice to live “off the grid.” For reasons both personal and financial, these people have opted to make a life for themselves without electrical power, sewers, or an indoor water system. This way of life takes a great deal of planning, organization and    commitment   , but once the system is in place, it is a relatively simple and cheap way to live. Of course, it is easier to live off the grid in a warm climate, but if extra heat is needed, it can be provided by a woodstove. Some people even grow grass on their roofs to insulate their homes. The heat from the sun’s rays can be collected through solar panels and converted into usable power, replacing the need for electricity. A well can be located outside, as in days of old. Living off the grid is not for the lazy, as a certain amount of upkeep and maintenance must be done. But for those who have made it work, it is a way of life from which they will never turn back.
【題組】1. People who live off the grid have learned to live without______ .
(A) heat
(B) currency
(C) electricity
(D) gasoline