Concept:Human trafficking is the illegal trade of people for the purpose of exploitation.
Explanation:Victims of human trafficking are recruited, transported, or harboured by force, fraud, or deception.
The main aim of traffickers is to exploit their victims for economic gain.
Victims lose their freedom and are made to work under threats, violence, or manipulation.
Such work is never voluntary; it is imposed on them against their will.
This compulsory exploitation is known as forced labour.
Human trafficking also includes sexual slavery and commercial sexual exploitation.
The other options do not fit because they describe voluntary or lawful activities.
Lucrative employment offers good pay and willing participation.
Visiting tourist sites and part-time studies are normal, voluntary activities.
None of these match the nature of trafficking, where victims have no choice.
Therefore, victims of human trafficking are always compelled to engage in forced labour.
Answer:D. forced labour