Final answer:
Lithium/barium base greases are suitable for high temperatures and high-speed applications in ball and roller bearings and are water-soluble, making them the best option for the given scenario.
Step-by-step explanation:
The semi-solid lubricant that is suitable for use with high temperatures and high-speed ball and roller bearings but soluble in water is D) Lithium/barium base greases. These greases are specifically designed to withstand both high temperatures and the shear forces found in such applications. Lithium and barium soap greases have good water resistance and are able to maintain their consistency under a high thermal range, making them the best choice for the scenario described. On the other hand, aluminum, sodium, and calcium base greases have different properties that may not make them as suitable for high-temperature and high-speed conditions combined with water solubility requirements.