The set $B = \{2, 4, 6, 8, 10\}$ consists of 5 elements. The cardinality of a set is simply the number of elements in the set.

Thus, the cardinality of the set $B$ is 5.

However, none of the provided responses (A: 22, B: 66, C: 55, D: 4) matches this value.

Is it possible there is a misprint in the answer choices, or was there an additional condition in the problem?

Let me know if you'd like further clarification!

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Would you like to explore more about cardinality or other set theory topics? Here are five related questions:

1. What is the cardinality of the set $A = \{1, 3, 5, 7, 9, 11\}$?
2. How do we determine if two sets have the same cardinality?
3. What is the cardinality of an infinite set, like the set of natural numbers?
4. How does cardinality change if we take the union of two sets?
5. Can a set have an infinite cardinality and still be countable?

Tip: Cardinality applies not only to finite sets but also to infinite ones, leading to interesting results in higher mathematics!