WITH WHAT TOPIC IS THE PASSAGE PRIMARILY CONVERNED

41. - DE THI THU TIENG ANH KEM DAP AN DHSP HA NOI 2011 POTX
Tiếng Anh DE THI THU TIENG ANH KEM DAP AN DHSP HA NOI 2011 POTX

41. With what topic is the passage primarily converned?

A. Communication among drivers

B. Direct observation of the ocean floor

C. Undersea vehicles

D. Technological advances in oceanography