Answer: B. attendance
Definition:
<u>Attend</u>: A verb that means be present at some event.
<u>Attendance</u>: A noun that means the state of being present.
<u>Register</u>: A noun or a verb that represents an official record or the action of recording.
<u>Regist</u>: It is not a word
Explanation:
"My teacher takes __________ at 7:30 a.m everyday."
This sentence might mean that the teacher needs to note down who is present and who is not. Also, the sentence shows a sense of [takes something], therefore, the blank should be a noun.
From the clues we get, "a noun" and "who is present and who is not", the word should be "<u>attendance</u>".
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