Lithium
Hydrogen
Helium
Oxygen
Answer is Right!
Answer is Wrong!
The correct answer is C. Helium.
An alpha particle is a positively charged particle that is emitted from the nucleus of an atom during radioactive decay. It is composed of two protons and two neutrons, and has a mass of 4 atomic mass units (AMU). The nucleus of a helium atom is also composed of two protons and two neutrons, so an alpha particle is essentially the same as a helium nucleus.
The other options are incorrect because they are not composed of two protons and two neutrons. Lithium has three protons and four neutrons, hydrogen has one proton and no neutrons, oxygen has eight protons and eight neutrons.