We are given a graph that shows the growth of a baby mouse over time.
On the x-axis, we have independent variable time (in days)
On the y-axis, we have dependent variable mass (in grams)
On the graph, the value of the independent variable at point A is the value of the time (in days)
The graph shows that the mass (in grams) of the baby mouse is increasing as the time (in days) increases.
Let us point out the value on the given graph,
As you can see, the value of the independent variable at point A is 6 days
Therefore, the answer is 6 days