Two point charges +Q and −Q are placed 5cm apart on a horizontal line. Which one of the following correctly describes the direction of the electric field lines in the region between the charges?
a) They are straight lines pointing away from both charges.
b) They form concentric circles centred on the midpoint between the charges.
c) They start from +Q and end on −Q, bending toward −Q as they approach it.
d) They start from −Q and end on +Q, bending toward +Q.