The correct answer is A) Interlocking shroud tips. Power turbine blades, which are used in lower temperature applications such as marine propulsion, often feature interlocking shroud tips. This helps maintain blade alignment and prevent excessive vibration. In contrast, high temperature turbine blades, such as those found in jet engines, do not have this feature. High temperature turbine blades are typically solid blades with dovetail or bulb roots to withstand the extreme heat and stresses. The other answer choices (B, C, and D) are features common to both power turbine and high temperature turbine blades, and therefore do not distinguish the two.