Entity type P must be exactly one type of C1, C2, C3. It cannot belong to none of them. Which of the following ER diagrams corresponds to these specifications? (only a portion of the diagram has been visualized)! Select one alternative: C4 C5 d C1 C2 C3 o C4 C5 o C1 C2 C3 0 d P C4 C5 d C1 C2 C3 o C4 C5 o C1 C2 C3 o d