The construct that had no DNA deleted from the enhancer was the control treatment in this experiment. Hence the correct option is b.
In the context of the experiment, the control treatment is a crucial component designed to serve as a baseline or reference point against which other experimental conditions are compared. In this case, the control treatment is represented by the construct that had no DNA deleted from the enhancer region.
By keeping the enhancer intact in this control group, researchers aim to observe and establish a baseline level of gene expression or activity associated with the unaltered enhancer.
This control is essential for accurate interpretation of the experimental results because it allows researchers to discern the specific impact of enhancer deletions on the expression of the reporter gene. Comparing the experimental constructs with deleted enhancer segments to the control construct helps isolate the effects of enhancer modifications from other variables.
This approach enables researchers to draw meaningful conclusions about the enhancer's role in regulating gene expression, providing valuable insights into the molecular mechanisms underlying the observed outcomes in the study. Hence the correct option is b.