Learning outcomes aim at

Learning outcomes are the specific competencies, knowledge, and skills a learner is expected to demonstrate by the end of a defined period of instruction; they function as the benchmark curriculum designers and teachers use to judge whether teaching has achieved its intended purpose.

Because outcomes are stated as the competencies to be demonstrated, their purpose is to ensure that every learner, not just the most or least able, acquires those defined competencies by the end of instruction. This is exactly what "ensuring all the competencies are acquired by learners" describes.

Why the other options fall short:

• Output-oriented learning is a general instructional stance about results, not a definition tied to learners' expected competencies.

• Achieving maximum levels of learning refers to how far a learner personally can go, which varies between learners rather than describing a common expectation.

• Achieving minimum levels of learning refers to a pass/fail threshold a learner must clear, which is a narrower idea than what learning outcomes actually specify.