What one problem would you like to see solved by science, and why?

Using science to solve the world’s problems

What one problem would you like to see solved by science, and why? It can be anything a disease, an environmental issue, even finding life on other planets Be specific for example, if you pick a disease, be specific if there’s more than one form of that disease. Also, think globally (would the biggest problems in the U.S. be the same problems around the world?).