Based on the field lines, the electric charges indicated
by the question marks are
the same
opposite

The same

Explanation:

The figure is missing: find it in attachment.

The electrostatic force between two charged particle is:

- Attractive if the two particles have opposite sign charge

- Repulsive if the two particles have same-sign charge

Moreover, a single-point charge produces a radial electric field, whose direction is as follows:

- The field lines point away from a positive charge

- The field lines point towards a negative charge

In the figure attached, we see that:

- The field lines point away from both charges

Therefore, this means that both charges are positive: so, the two charges are the same.