Answer:
the answer is "Dr. Salk has traveled and given the polio vaccine to children in foreign countries."
Step-by-step explanation:
Since A(Dr. Salk has assisted foreign countries by providing technical information, Dr. Salk has helped foreign countries begin to produce the vaccine themselves, and Dr. Salk has offered foreign scientists the opportunity to tour his laboratory are true, due to:
"The work of Dr. Salk is in the highest tradition of selfless and dedicated medical research. He has provided a means for the control of a dread disease. By helping scientists in other countries with technical information; by offering to them the strains of seed virus and professional aid so that the production of vaccine can be started by them everywhere; by welcoming them to his laboratory that they may gain a fuller knowledge, Dr. Salk is a benefactor of mankind."
The answer "Dr. Salk has traveled and given the polio vaccine to children in foreign countries." would be correct and also because it is not stated in the text.
Sorry if wrong but im sure! Have a good day!