阅读短文,下列问题

    Today is Saturday. It is Children's Day, I get up very early. I go to school at about six. Our school is very cleanand beautiful. Birds in the trees sing all the time. Every student wears a white coat. Girls wears beautiful skirts. We sing and dance, run and jump. We look like happy birds.

    Our party begins at half past seven. First, we listen to our teachers, and then the programme(节目) begins. Many people sing together on the stage(舞台) . They sing and dance very well. All the teachers and students like watching and listening to them. After the party we play games in the classroom. All of us enjoy the day very much.

如图所示，烧杯内盛有某种液体（是下表所列液体中的一种），液体中的试管内盛有水.在1个标准大气压下，若对烧杯的底部持续加热，最终发现试管内的水也能发生沸腾，则烧杯内盛的液体应是 （）