Question

Which of the following is not a fundamental particle?
A. Electron
B. Proton
C. Neutron
D. X-rays

Answer 1

Protons and neutrons are made up of fundamental particles of matter called quarks. Electrons are another type of fundamental particle of matter called leptons. Bosons are fundamental particles that carry forces between fundamental particles of matter.

Complete step by step answer:
In particle physics, an elementary particle or fundamental particle is a subatomic particle with no substructure, i.e. it is not composed of other particles.
X-rays are a form of electromagnetic radiation, similar to visible light. Unlike light, however, x-rays have higher energy and can pass through most objects, including the body. Medical x-rays are used to generate images of tissues and structures inside the body.
X-rays are not particles, they are electromagnetic waves having higher energy than UV and less energy than gamma rays. So, they are not fundamental particles.

So, the correct answer is Option D.

Additional information:
Leptons are divided into three pairs. Each pair has an elementary particle with a charge and one with no charge – one that is much lighter and extremely difficult to detect. The lightest of these pairs is the electron and electron-neutrino.
The charged electron is responsible for electric currents. Its uncharged partner, known as the electron-neutrino, is produced copiously in the sun and these interact so weakly with their surroundings that they pass unhindered through the Earth.

Note: One type of x-ray detector is photographic film, but there are many other types of detectors that are used to produce digital images. The x-ray images that result from this process are called radiographs.