Where does the lymphatic tubes discharge their contents?

Concept: One of the subclavian veins receives lymph from a lymph duct, a large lymphatic tube. The right lymphatic duct, as well as the thoracic duct, are the two lymph ducts in the body. 

The right upper limb, the right-hand side of the thorax, and the right sides of the head and neck all have lymphatic drainage systems. 

In between the left subclavian and left internal jugular veins, at the left brachiocephalic vein, the thoracic duct discharges lymph into the circulatory system.

Hence, option 3 is correct answer