The correct answer is option 'D', which states that for efficient and durable learning, the learner should have the desired level of ability and motivation.

Explanation:

1. Ability to learn:
- In order for learning to be efficient and durable, the learner must possess the necessary ability to comprehend and process new information.
- This includes cognitive abilities such as memory, attention, problem-solving skills, and critical thinking.
- Without the ability to learn, the learner may struggle to understand and retain the information being presented.

2. Level of motivation:
- Motivation plays a crucial role in learning, as it determines the learner's level of interest, engagement, and effort.
- A learner with a high level of motivation is more likely to actively participate in the learning process, seek out additional resources, and persist in the face of challenges.
- On the other hand, a learner with low motivation may exhibit disinterest, lack of effort, and limited engagement in the learning activities.

3. Desired level of ability and motivation:
- It is important for the learner to have both the desired level of ability and motivation for efficient and durable learning.
- Having the desired level of ability ensures that the learner has the necessary cognitive skills to understand and process new information effectively.
- Similarly, having the desired level of motivation ensures that the learner is actively engaged and invested in the learning process, which enhances information retention and application.

Conclusion:
In conclusion, for efficient and durable learning to take place, the learner should possess the desired level of ability and motivation. This combination allows the learner to effectively comprehend and process new information, as well as actively engage in the learning process, leading to improved learning outcomes.