Robert Hooke, a famous 17th century English scientist, published a book of sketches such as the one above. What recent invention made these observations possible?

The correct answer to this open question is the following.

Although you forgot to include the sketches and the options of the question, we can say the following.

Robert Hooke, a famous 17th-century English scientist, published a book of sketches such as the one above. The recent invention that made these observations possible was the microscope.

Robert Hooke was an English scientist who wrote the treatise called "Micrographia." In this work, he helped design a modern microscope for that time with better lenses and improved optical characteristics that facilitated scientific research. In the end, it was Christopher C*ck, the one who fabricated the new microscope.

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