Answer: C) The tone of the speech was stern; the speaker called for hard work and determination.
Explanation: when we have two clauses, we use a comma when we have a conjunction (and, but, or, etc) between them, and we use a semicolon if we have two independent clauses connected without a conjunction. So the correct answer is option C: The tone of the speech was stern; the speaker called for hard work and determination, in which we have two independent clauses without any conjunction, so we use a semicolon.
Answer:
when', 'after', 'although', 'before', 'if', '
