Answer:
D. hot, but much cooler than at a hydrothermal vent
Step-by-step explanation:
A cold seep is an area in the ocean floor where hydrogen sulfide, methane and other hydrocarbon rich fluids seep through thus forming a brine pool.
A cold seep is also called a cold vent and its temperature is not necessary lower than that of the surrounding water, but it is lower than that of a hydrothermal vent which is about 60 °C.