Answer: (A) Efficiency
Step-by-step explanation:
According to the given question, Nate is start learning swimming and he needs improvement based on his efficiency as it is the ability for producing the desirable result by avoiding all the negative circumstances.
As, Nate always splash water on lifeguard during the swimming so that is why he improves his performance more efficiently.
The efficiency is the process that reduce or avoid all the unnecessary resources like physical material and helps in achieving the high result. Therefore, Option (A) is correct.