An in-depth study of the individual in terms of his/her psychological attributes, psychological history in the context of his/her psycho-social and physical environment is known as:

The correct option is Case-study.

Explanation:
A case study is an in-depth, detailed, and comprehensive investigation of a single individual, group, or event. It is characterized by its holistic approach, examining a wide range of factors to understand the complexities of human behavior. This includes analyzing the individual's unique psychological attributes, their personal and clinical history, and how they function within their specific psycho-social and physical environments.
Let us examine why this is the correct choice compared to the other options:

1. Case-study: This method integrates information from multiple sources (such as interviews, observations, and historical records) to create a complete profile of the subject in their natural context.
2. Interview: An interview is a specific data-gathering technique involving face-to-face or virtual interaction. While it can be a tool used within a case study, it is not the overall study of the individual in context.
3. Self-report: This is a method where individuals describe their own feelings, attitudes, or beliefs (typically via questionnaires or diaries). It relies solely on the individual's perspective and lacks the multi-dimensional environmental analysis of a case study.
4. Psychological test: This is a standardized tool designed to measure specific cognitive, emotional, or behavioral traits. It provides quantitative scores rather than a comprehensive historical and environmental narrative.