Concept:
Social inequality exists when resources, opportunities, and privileges are distributed unequally among people in society.
Step 1:
The assertion correctly explains that unequal distribution of resources such as wealth, education, health, and power is called social inequality.
\[
A \text{ is correct}
\]
Step 2:
Prejudice, stereotypes, discrimination, and social exclusion are actually expressions of social inequality.
\[
R \text{ is incorrect}
\]
Step 3:
Therefore, Assertion is true but Reason is false.
\[
\boxed{\text{(3) (A) is correct but (R) is not correct}}
\]