Step 1: Understanding Environmental Impact Assessment (EIA).
Environmental Impact Assessment (EIA) is a systematic process used to identify, predict, and evaluate the potential environmental effects of a proposed project before decision-making and project approval. It helps in ensuring that environmental considerations are integrated into development planning.
Step 2: Purpose of the first step in EIA.
Before conducting a detailed environmental study, it is necessary to decide whether a proposed project actually requires an EIA or not. This avoids unnecessary assessment for projects with negligible environmental impact and focuses resources on significant projects.
Step 3: Explanation of Screening.
Screening is the initial step of the EIA process. In this stage, the project is examined to determine whether it falls under categories that require environmental clearance and the level of assessment needed (full EIA, partial EIA, or no EIA).
Step 4: Analysis of options.
(A) Impact evaluation: This is carried out after impacts have been identified and predicted, not at the beginning.
(B) Public hearing: This occurs at a later stage to obtain public opinion on the proposed project.
(C) Screening: Correct — It is the very first step used to decide whether an EIA study is required.
(D) Mitigation: Mitigation measures are proposed only after environmental impacts have been assessed.
Step 5: Final conclusion.
Since screening is used to decide the necessity and extent of environmental assessment at the very beginning of the EIA process, the correct answer is (C) Screening.