A -- Advanced mathematics B -- Experiment of college physics
C -- Linear algebra D -- Fundamentals of law
E -- Information searches F -- Satellite communications
G -- Specialty english H -- Microwave technique
I -- Theory of circuitry J -- Signal & linear system
K -- Metalworking practice L -- Electrical engineering practice
M -- Principle of microcomputer N -- Moving communication
O -- Basis of software technique
专业英语 ( )金工实习

A sunny day in winter is colder than a sunny day in summer. This is because the summer day is longer, everything has a longer time to warm up and the sun shines more directly on the earth. In winter, the day is short, there is less time for everything to get warm and the sun doesn’t shine more directly on the earth.Land, just like the sand, warms up more quickly than water but it also loses its heat more quickly. So on a hot sunny summer’s day on the beach, you can feel how hot the sand gets. The water is cool to the feet when you go for a paddle. The sun makes our earth beautiful. It gives us light. It keeps us warm. It makes things grow. We cannot live without the sun.

A．there is not enough water on earth
B．the demand for water keeps increasing; the amount of water remains the same
C．population growth in some courtiers continues to increase
D．the population in countries that lack water is growing fast