The answer to your question is letter A
A - Although he denies them, Dr. Vasequez faced several scandals last year.
A complex sentences must have both a dependent clasuse (although he denies them) and an independent clause (Dr. Vasquez faced several scandals last year.
Options B and D are compound sentences (two independent clauses) and option C is a simple sentence.
The answer is C, CHIUNE: And if the Nazis find out . . . You and the children must return to Tokyo immediately. <span>
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