Question Detail
Question
Which specific device was discovered by Ruska in 1931, as mentioned in the summary of key milestones?
Correct Answer
Option B is the correct answer.
Detailed Explanation
The 'Summary of key milestones' includes: '1931: Electron Microscope(Ruska)'.
Hint
Look at the bulleted 'Summary of key milestones' and the year 1931.