What part of speech is because in this sentence you were late received a tardy slip?

In the sentence "You were late because you received a tardy slip", the word "because" is a subordinating conjunction.

Here's why:

* It connects two clauses: "You were late" and "you received a tardy slip".

* It shows a cause-and-effect relationship: The second clause (receiving a tardy slip) is the reason for the first clause (being late).

* It makes the second clause dependent on the first: The second clause can't stand alone as a complete sentence.

Therefore, "because" acts as a bridge between the two clauses, indicating the reason for the situation.