Answer :
Answer:
In a paper on photosynthesis in a desert cactus, the section where you would find a review of existing knowledge relevant to the experiment is the Introduction.
Explanation
1. **Introduction**: This section sets the stage for the research by providing background information, context, and a literature review of existing knowledge relevant to the topic of the experiment. It outlines the research problem, its significance, and the objectives of the study. Researchers usually summarize what is already known about the subject and explain how their study builds upon or contributes to existing knowledge in the field. By reviewing the existing knowledge in the introduction, the researchers establish the rationale for their study and demonstrate the gap in knowledge that their research aims to fill. This helps readers understand the significance of the experiment and its potential contributions to the scientific community.
