Final answer:
The elevation of the second trench is -7,588 meters below sea level.
Step-by-step explanation:
The elevation of the first ocean trench is -10,796 meters below sea level. The bottom of the second trench has an elevation 3,208 meters higher than the first trench. To find the elevation of the second trench, we need to add 3,208 to -10,796. This gives us a final elevation of -7,588 meters.
Therefore, the answer is A. -7,588 meters.