Final answer:
The correct answer is option (a). The approximate water temperature at a depth of 125 meters is likely to be around or below 4°C due to the decrease in temperature with depth, but of the given choices, 12°C might be the closest approximation.
Step-by-step explanation:
The question asks to identify the approximate water temperature at a depth of 125 meters. The temperature of water at a specific depth can vary greatly depending on geographical location, season, and local environmental conditions.
However, typically, as one goes deeper into the water, the temperature tends to decrease due to the lack of sunlight penetration and the thermocline effect which causes stratification in water bodies.
Without specific regional data, we cannot provide a precise temperature. However, in many parts of the ocean, the temperature is likely to be around or below 4°C at such depths because, beyond the thermocline, temperature decreases with depth.
Based on general oceanographic knowledge, option a) 12°C could be the closest answer of the given choices, although it might still be higher than the actual temperature which could be even lower than 10°C or approaching 4°C in some regions.