Will mark brainliest !

To help prevent people from getting the Ebola virus, countries around the world paid to help doctors develop a new vaccine. Now that the vaccine has been made, doctors will need to experiment on a large number of people to find out if it works safely.

What is the greatest limitation that scientists are dealing with as they try to figure out how to experiment with the Ebola vaccine?

time
complexity
money
ethics

A. Time

Explanation: It takes a lot of time for doctors and scientists to figure out what is used to make vaccines for certain viruses or diseases such as Ebola or the Coronavirus. Once they've gathered all of the information, they can put all of the materials or chemicals together to make the vaccine.

Is ethics

Explanation:

Because the great limitation people can get by preventing ebola virus is ETHICS

answer : haversian

[explanation: -(compact bone is organized as parallel columns, known as haversian systems, which run lengthwise down the axis of long bones. these columns are composed of lamellae, concentric rings of bone, surrounding a central channel, or haversian canal, that contains the nerves, blood vessels, and lymphatic system of the bone)]