Which of the following is a correct statement?

Options

A. (a) Beta rays are same as cathode rays
B. (b) Gamma rays are high energy neutrons
C. (c) Alpha particles are singly ionized helium atoms
D. (d) Protons and neutrons have exactly the same mass

Explanation

To determine which of the following statements is correct, we will analyze each statement one by one:

1. **Beta rays are the same as cathode rays.**
- Beta rays are indeed high-energy electrons emitted from a radioactive decay process. Cathode rays are streams of electrons observed in vacuum tubes. Therefore, this statement is correct.

2. **Gamma rays are high-energy neutrons.**
- This statement is incorrect. Gamma rays are actually high-energy electromagnetic waves, not neutrons.

3. **Alpha particles are singly ionized helium atoms.**
- This statement is also incorrect. Alpha particles consist of two protons and two neutrons, which is equivalent to a doubly ionized helium atom (He²⁺), not singly ionized.

4. **Protons and neutrons have exactly the same mass.**
- This statement is incorrect. While protons and neutrons have similar masses, they are not exactly the same. The mass of a neutron is slightly greater than that of a proton.

Based on the analysis, the only correct statement is:

**Answer: Beta rays are the same as cathode rays.**