To find the apparent percentage dissociation of Na2SO4, we need to consider the concept of isotonic solutions and use the formula for apparent percentage dissociation.

Isotonic Solutions:
Isotonic solutions are those that have the same osmotic pressure. In other words, they have the same concentration of solute particles per unit volume. In this case, we have a 0.004 M solution of Na2SO4 and a 0.010 M solution of glucose.

Apparent Percentage Dissociation:
The apparent percentage dissociation is a measure of the extent of dissociation of a solute in a solution. It is defined as the ratio of the concentration of dissociated particles to the initial concentration of the solute, multiplied by 100.

To calculate the apparent percentage dissociation of Na2SO4, we can use the following formula:

Apparent % dissociation = (Concentration of dissociated particles / Initial concentration of Na2SO4) x 100

Let's proceed with the calculations:

1. Calculate the number of particles produced by Na2SO4:
Na2SO4 dissociates into 2 Na+ ions and 1 SO4^2- ion.
So, the total number of particles produced by Na2SO4 is 3.

2. Calculate the concentration of dissociated particles:
Since the solution is isotonic with a 0.010 M glucose solution, the concentration of solute particles in both solutions should be the same.
For glucose, the concentration of solute particles is 0.010 M.
Therefore, the concentration of dissociated particles of Na2SO4 should also be 0.010 M.

3. Calculate the initial concentration of Na2SO4:
The initial concentration of Na2SO4 is given as 0.004 M.

4. Calculate the apparent percentage dissociation:
Apparent % dissociation = (0.010 M / 0.004 M) x 100 = 250%

Therefore, the apparent percentage dissociation of Na2SO4 is 250%.

However, none of the provided answer options match the calculated value of 250%. Please double-check the question or provide additional information if necessary.