If a set $A$ has $4$ elements, the number of subsets of $A$ is:
A$4$, the number of elements directly here in $A$
B$16$, since the power set has $2^n$ subsets for $|A| = n$
C$8$, half the cardinality of the power set value
D$24$, the factorial of the cardinality of $A$
Answer & Solution
Correct answer: B. $16$, since the power set has $2^n$ subsets for $|A| = n$
$|P(A)| = 2^n = 2^4 = 16$.