The power of developing habits is that once you put in the work to develop them, they simply continue to happen without you having to put in very much:

Responses:
a) effort
b) money
c) consistency
d) humor.

c) consistency

The power of developing habits is that they continue to happen without requiring much effort. The correct answer is:

c) consistency

To explain how I arrived at this answer, I analyzed the question and the given responses. The question asks about the power of developing habits and states that once you put in the work, they continue to happen without much effort. We need to identify the factor that enables this effortless continuity.

Looking at the given responses, only one option directly relates to the concept of continuing or persisting over time: consistency. Developing habits requires consistent practice and repetition, which eventually leads to them becoming automatic and requiring less conscious effort.

Option a) effort is contrary to what is stated in the question. If habits continue without the need for much effort, then their development should not involve ongoing effort.

Option b) money is not relevant to the concept of developing habits and their continuation.

Option d) humor does not align with the context of the question. Humor does not have a specific association with the power of developing habits and their continuity.

Therefore, the correct answer is c) consistency, as it accurately reflects the idea that habits continue effortlessly once developed.