For the electric field shown, which of the following statements describes an increase in voltage?

A) A negative charge crosses an equipotential line toward the source charge.
B) You cannot tell from the information given.
C) A positive charge crosses an equipotential line toward the source charge.
D) A positive charge moves along an equipotential line.

UPDATE: ANSWER IS C

The correct answer is: Option (C) A positive charge crosses an equipotential line toward the source charge.

Explanation:
The red circles drawn are the equipotential circles. It means that on the line of the circle the work that YOU have done from bringing the positive test charge from infinity to every point on the line of the circle is same. Imagine you are moving towards the source charge from very far away. The more you move towards the source charge the more you will experience the force on you due to the increasing electric field near the charge and the more POSITIVE work you do. It means the work increases and in Electromagnetism that work is translated as the voltage. Hence a positive charge crosses an equipotential line toward the source charge with the increase in voltage. Therefore the correct option is (C).