## **Core Concept**
Radium is a radioactive alkaline earth metal element with the symbol Ra and atomic number 88. It decays by emitting alpha, beta, and gamma radiation. The question pertains to the type of radiation emitted by radium.

## **Why the Correct Answer is Right**
Radium primarily emits **alpha (α) radiation**. Alpha radiation consists of high-energy helium nuclei, which are emitted from the nucleus of an atom during certain types of radioactive decay, including alpha decay. Radium-226, a common isotope of radium, undergoes alpha decay to form radon-222.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Beta (β) radiation is a type of ionizing radiation emitted by certain types of radioactive nuclei, but it is not the primary type of radiation associated with radium.
- **Option B:** Gamma (γ) radiation is also emitted by radium, but like beta radiation, it is not the primary type of radiation.
- **Option D:** This option is blank and does not pertain to any type of radiation.

## **Clinical Pearl / High-Yield Fact**
Radium's radioactive properties make it historically significant in medicine, particularly in the treatment of cancer. However, its use has declined due to safer alternatives. A key point to remember is that alpha particles have high ionization potential but low penetration, being stopped by a sheet of paper or human skin.

## **Correct Answer:** .