Read the text and determine if the sentence is true (see options at the end):

In probability theory, the sample space of an experiment or random trial is the set of all possible outcomes or results of that experiment. A sample space is usually denoted using set notation, and the possible ordered outcomes are listed as elements in the set. It is common to refer to a sample space by the labels "S", Ω, or "U" (for "universal set").

Sentence: probability theory is a theory on experiments.
Available choices:
 +Yes;
 +It's impossible to say;
 +No;