Answer : 1. "W.C. roentgen"
Explanation :

Wilhelm Conrad Röntgen, a German physicist, discovered X-rays in 1895. While conducting experiments with cathode-ray tubes, he observed a new and mysterious form of radiation. Röntgen termed this radiation "X-rays" as their nature was initially unknown. He found that these rays could pass through various materials and create images of the internal structures of objects, including the bones of the human body.

Röntgen's discovery revolutionized medical imaging and had far-reaching implications in various scientific and technological fields. For his groundbreaking work, Röntgen was awarded the first Nobel Prize in Physics in 1901.