The question asks to identify the term that describes educational settings where learners work together on a shared task, are actively involved, and are responsible for their own learning as well as contributing to the group's success. This requires understanding different pedagogical approaches.

Understanding Collaborative Learning Environments

Let's break down the key elements mentioned in the question:

• Methodologies and environments: Refers to specific ways of teaching and learning, and the setting where it happens.
• Learners engage in a common task: Students work together on the same activity or project.
• Each individual finds out: Implies active participation and personal discovery or understanding.
• Is accountable to each other: Highlights mutual responsibility and interdependence among group members.

This description strongly points towards a learning method where interaction and mutual support are central to achieving a goal.

Analyzing the Options

Let's look at the provided options:

1. Co-operative learning: This involves learners working together, often with structured roles and clear individual accountability, towards a common goal. It shares similarities with the description.
2. Learning centred learning: This is a broad term focusing on shifting the focus from the teacher to the learning process itself, emphasizing the learner's experience and active role. It doesn't specifically require group interaction and mutual accountability in the way described.
3. Collaborative learning: This approach involves learners working together in groups to solve a problem, complete a task, or create a product. It emphasizes shared responsibility, peer interaction, negotiation of meaning, and mutual accountability, where the success of the group depends on the contribution of each member and members support each other. The phrase "each individual finds out and is accountable to each other" is a core characteristic.
4. Learner centred learning: Similar to learning centred learning, this approach focuses on the needs, interests, and experiences of the learner, putting them at the center of the educational process. While it encourages active participation, it doesn't inherently imply group work with mutual accountability as described.

Comparing the definition provided in the question with the options, collaborative learning most accurately matches the description of methodologies and environments where learners engage in a common task, actively find out information, and are accountable to each other.