Surrounding every moving electron is:

• A. an electromagnetic field
• B. a layer of positrons
• C. a neutron cloud
• D. a shell of protons

Answer: (A)

Verified step by step guidance

1. Understand the nature of an electron: it is a charged particle that moves and generates an electric field around it.
2. Recall that a moving charged particle produces both an electric field and a magnetic field, which together form an electromagnetic field.
3. Recognize that positrons are the antiparticles of electrons and are not naturally surrounding electrons in normal conditions.
4. Note that neutrons are neutral particles found in the nucleus and do not form clouds around electrons.
5. Understand that protons are positively charged particles in the nucleus and do not form shells around electrons; thus, the correct concept is the electromagnetic field surrounding a moving electron.