Please answer the following question: Answer the following question given this paragraph: Viruses were assumed to exist before they were first seen with an electron microscope in the 1930s. Multiple hypotheses for viral origins have been proposed. Q: Viruses were assumed to exist before they were first seen with an electron microscope in which decade? Choices: - 1960's - 1890's - 1940's - 1930 ' s A:
Answer:
1930 ' s