identify the charge(s) with increasing electric potential energy. identify the charge with decreasing…

Explanation:

Step1: Recall electric - potential - energy concept

The electric potential energy of a charge $q$ in an electric field $E$ is given by $U = qV$, and the direction of the electric field is from high to low potential. A positive charge moves from high to low potential and its potential energy decreases, while a negative charge moves from low to high potential and its potential energy increases.

Step2: Analyze charge A

Charge A is a positive charge moving in the direction of the electric field. Since $U = qV$ and for a positive $q$, as it moves in the direction of the electric field (towards lower potential), its electric - potential energy $U$ decreases.

Step3: Analyze charge B

Charge B is a negative charge moving in the direction of the electric field. For a negative $q$, as it moves in the direction of the electric field (towards lower potential), its electric - potential energy $U$ increases.

Step4: Analyze charge C

Charge C is a positive charge moving against the direction of the electric field. For a positive $q$, as it moves against the electric field (towards higher potential), its electric - potential energy $U$ increases.

Step5: Analyze charge D

Charge D is a negative charge moving against the direction of the electric field. For a negative $q$, as it moves against the electric field (towards higher potential), its electric - potential energy $U$ decreases.

Answer:

Charge with increasing electric - potential energy: B, C Charge with decreasing electric - potential energy: A, D Charge with constant electric - potential energy: None