The correct answer is C. pliability.
Pliability is the ability to bend or be bent easily. In the context of planning for an unpredictable future, pliability refers to the ability to adapt to change. This is important because the future is uncertain, and what we think will happen may not actually happen. By being pliable, we can adjust our plans as needed to ensure that we are still on track to achieve our goals.
The other options are not as relevant to planning for an unpredictable future. Complexity refers to the number of parts or elements that make up something. This is not necessarily a bad thing, but it can make it more difficult to understand and predict how something will behave. Tension refers to a state of mental or emotional strain or suspense. This can be a negative thing, as it can make it difficult to think clearly and make decisions. Rigidity refers to the quality of being firm or stiff. This can be a positive thing in some situations, but it can also make it difficult to adapt to change.
In conclusion, the key words in planning for an unpredictable future are focus and flexibility. Pliability is the ability to bend or be bent easily, which is important because the future is uncertain and we need to be able to adapt to change.