Answer: (d) Assumption of conclusions without prior experimentation or observation.
Step-by-step explanation:
A scientific investigation can be define as a fact finding inquiry which involves the detailed step by step procedure for answering the questions related to science. It involves steps like making an observation, creating a hypothesis, making a prediction depending upon the hypothesis, experimentation and analysis.
(d) Assumption of conclusions without prior experimentation or observation. is the correct option this is because of the fact that in a scientific investigation an assumption cannot be made. The assumption cannot lead to conclusive results and finding cannot be considered as reliable.