Event "P or Q" is represented by:

Correct option is D

In probability theory:
"P or Q" means the event that either P occurs, or Q occurs, or both occur.
This is mathematically represented by the union of two events:

P or Q = P∪Q
Where:
∪ denotes the union of two sets.
The union includes all outcomes that are in P, in Q, or in both.

​$$\begin{aligned}&\text{Important points:} \\&\bullet \ P \cap Q' = \text{"P and not Q"} \\&\bullet \ P \cap Q = \text{"P and Q"} \\&\bullet \ P' \cap Q = \text{"not P and Q"}\end{aligned}$$​​