下列各句中，标点符号使用正确的一项是(　　)

The teacher, with 6 girls and 8 boys of her class, ________visiting a museum when the earthquakestruck.[ ]

When did you leave the office yesterday afternoon—____ I finished my work.

Is that girl in red ,Sally—No, it_______ be her. She has gone to Hong Kong.

To reduce emissions of greenhouse gases, many countries are increasing the use of natural gas, wind and other forms of _______ energy.