Why can consent be doubtful in human trafficking?

Correct answer: Because there may be deception threat or control over the person

The direct answer is B: there may be deception, threat, or control over the person. Consent is meaningful only when it is free, informed, and given without force or manipulation. In trafficking, a person may be lured with a false job, threatened with harm, have identity documents taken, be isolated, or be controlled by debt or another person. Step by step: trafficking involves exploitation; exploitation commonly uses pressure or deception; pressure and deception prevent a genuinely free choice; therefore apparent agreement may not be real consent. Option A is wrong because consent is not always written; even written words may be obtained through fear or deception. Option B is correct because it identifies the conditions that make consent doubtful. Option C is wrong because lawful employment is not automatically wrong; the problem is force, deception, abuse, or exploitation. Option D is wrong because travelling itself is not a crime; trafficking may involve movement, but the crime is exploitation and control, not ordinary travel. Exam cue: always ask whether the person had a real and free choice.