Given the sets:

$A = \{2, 4, 6, 8, 10, 12, 14, 16, 18, 20\}$ $B = \{10, 12, 14, 16, 18\}$

Let's evaluate the options:

1. $A = B$: This statement is false because $A$ and $B$ do not have the same elements. Set $A$ has 10 elements, while set $B$ has only 5 elements.

2. $A \cong B$: This symbol, when used in set theory, typically refers to isomorphism, which is not meaningful for basic set equality or subset relations. Thus, this statement is neither applicable nor true in this context.

3. $A \subseteq B$: This is false because $A$ contains elements that are not in $B$ (e.g., 2, 4, 6, 8, 20).

4. $B \subseteq A$: This statement is true because every element in $B$ (10, 12, 14, 16, 18) is also in $A$.

Hence, the correct statement is:

$B \subseteq A$

Would you like to go over any specific option in more detail or have any further questions?

Related Questions

1. What is the definition of a subset and a proper subset?
2. How can we visually represent the relationship between $A$ and $B$?
3. What is the difference between equality and subset relations in set theory?
4. What does $A \cong B$ usually denote in mathematical contexts outside of set theory?
5. What are other set operations that can be applied to $A$ and $B$?

Tip: To verify $B \subseteq A$, check if all elements of $B$ are in $A$. This ensures that $B$ is indeed a subset of $A$.