The diagram shows the electric field lines around two charges. based on the field lines, what is the best description of the charges ? a.) they are negative, and they repel b.) the left is negative and the right is positive, so they attract. c.) the left is positive and the right is negative, so they attract. d.) they are positive, they repel

The correct answer is D.) they are positive, they repel.

The law of charges states that; like charges repel while unlike charges attract. 
∴ The first conclusion we can make from the two charges is that they are like, the repel. 

Magnetic field lines moves from positive to negative. In the diagram it is clear that the fields are moving from the two charges. 

So therefore, the correct answer is that, the two charges are positive and they repel.