Final answer:
Treatment cocktails of multiple drugs, like HAART for HIV, are more effective than single-drug treatments because they make it harder for the virus to develop resistance.
Step-by-step explanation:
The statement that treatment "cocktails" made of multiple drugs do not increase effectiveness of therapy is false. In fact, when treating certain conditions like HIV, a mixture of drugs, known as a treatment cocktail, significantly increases the effectiveness of the therapy. The use of Highly Active Antiretroviral Therapy (HAART), which includes multiple drugs, makes it more challenging for the virus to develop resistance versus when a single drug is used due to its high mutation rate. Thus, cocktails consisting of multiple drugs are essential to combatting diseases like HIV effectively.