What does 'refuse' mean?

[Stupy]

English Language Tests, Intermediate level

ESL/EFL Test #840 "Rewriting Sentences (2)", question 1

Given that you refuse to come to class, I have no choice but to fail you.
I have to fail you ......... you refuse to come to class.

(a) so
(b) because
(c) before
(d) unless

English Language Tests, Intermediate level

ESL/EFL Test #840 "Rewriting Sentences (2)", answer 1

Given that you refuse to come to class, I have no choice but to fail you.
I have to fail you because you refuse to come to class.

Correct answer: (b) because
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what mean the words:refuse

[Beeesneees]

Have you tried looking it up in a learners' dictionary?

refuse
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Cheers m' dears!