Scenario Biomedical Scientists Have Recently Developed an Anticancer Drug Delivery System

Scenario
Biomedical scientists have recently developed an anticancer drug delivery system that sneaks the anticancer drug into cancer cells before releasing it. They were able to do this by using two sets of liposomes. An anticancer drug (Doxorubicin (Dox) ) bound to DNA molecules was added into one set of liposomes, and a high concentration of ATP molecules were added to the other set of liposomes. The drug is inactive when bound to DNA molecules. Researchers inject both types of liposomes into cancer cells, and upon doing so their contents are released. The ATP molecules from one set of liposomes bind to the DNA molecules from the other set of liposomes) and activate the drug, thus inducing cell death and decreasing tumor size.
Mice with breast cancer tumors were treated with this liposome system to test the effectiveness of the drug. The scientists performed three trials-one with both types of liposomes (Dox + ATP) , one with just the drug (Dox only) , and one with a salt solution (control) . Examine the figure below and answer the following questions.
-What would be the best experiment to test the effectiveness of this anticancer drug system?

A) Inject both sets of liposomes into a single healthy mouse and measure what happens to its blood ATP levels.
B) Inject both sets of liposomes into a single mouse that has tumors and measure what happens to the size of the tumors.
C) Inject both sets of liposomes into multiple healthy mice and measure what happens to their blood ATP levels.
D) Inject both sets of liposomes into multiple mice that have tumors and measure what happens to the size of the tumors.