Final answer:
The isotonic point on a graph is where equilibrium is reached, potentially represented by the C) minimum point. However, without specific context of the graph, it's not possible to determine its exact location in terms of intercepts or maximum/minimum values.
Step-by-step explanation:
The isotonic point on a graph is typically where the curve represents a state where the forces or concentrations inside and outside a cell are equal. This point could potentially be found at the minimum point of a graph if the graph is showing an active parameter changing over time or condition, reaching a state of equilibrium, and then possibly increasing or decreasing again. Another context to consider is osmosis, where the isotonic point indicates no net water movement across the cell membrane. However, based on the graph descriptions given, it is not possible to definitively assign the isotonic point to a specific part like the y-intercept, x-intercept, or the minimum point without more information about what the graph represents.