Answer: A. Observation
The scientific method is generally used when conducting experiments as well as for exploring observations. In order to discover the link or relationship between cause and effect in a variety of applications and situations, the scientific method has proven to be a standard in performing many experiments today. Observation entails asking questions on a natural phenomenon in order to formulate a hypothesis that will in turn, answer the question. To make observations, the human senses are well utilized and this sometimes makes the process ineffective as the human senses are extremely subjective leading to difficulty in comparing and recording.