Answer :
Final answer:
Alger Hiss, Julius Rosenberg, and Klaus Fuchs were individuals involved in espionage activities by passing secret information to the Soviets during the mid-20th century.
Explanation:
Alger Hiss, a former State Department official, was accused of passing top-secret papers to the Soviets based on allegations by Whittaker Chambers. Although espionage charges could not be pursued due to the statute of limitations, Hiss was convicted of perjury. Another notable case involved Julius Rosenberg and his wife Ethel, who were accused, found guilty, and executed for passing atomic secrets to the Soviets. Additionally, Klaus Fuchs, a British physicist, confessed to sharing America's atomic bomb information with the Soviets, expediting their development of the bomb.
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