To answer the question of which particles have no mass, we can analyze the properties of each option given:

1. **Electrons (a)**: Electrons have a very small mass, approximately $9.11 \times 10^{-31}$ kg. Thus, they do not fall under the category of particles with no mass.

2. **Photons (b)**: Photons are the particle form of light and are known to have zero rest mass. They always travel at the speed of light ($c$) in a vacuum.

3. **Neutrinos (c)**: Neutrinos are nearly massless particles, but they possess a tiny, non-zero mass. Thus, they do not have "no mass."

4. **Gluons (d)**: Gluons, which mediate the strong force in quantum chromodynamics, also have zero rest mass, much like photons.

5. **All of the above (e)**: This option suggests that all listed particles have no mass, which is not true since electrons and neutrinos have mass.

6. **None of the above (f)**: This option implies that none of the listed particles have no mass, which is not the case either, as both photons and gluons do.

### Conclusion:
The correct answer is **b. Photons** and **d. Gluons**. Both of these particles are massless. Therefore, while **"All of the above"** sounds appealing, it is incorrect because electrons and neutrinos do not fit the criteria.

### Final Answer
The particles that have no mass are **Photons (b)** and **Gluons (d)**.

Question

To answer the question of which particles have no mass, we can analyze the properties of each option given:

1. **Electrons (a)**: Electrons have a very small mass, approximately $9.11 \times 10^{-31}$ kg. Thus, they do not fall under the category of particles with no mass.

2. **Photons (b)**: Photons are the particle form of light and are known to have zero rest mass. They always travel at the speed of light ($c$) in a vacuum.

3. **Neutrinos (c)**: Neutrinos are nearly massless particles, but they possess a tiny, non-zero mass. Thus, they do not have "no mass."

4. **Gluons (d)**: Gluons, which mediate the strong force in quantum chromodynamics, also have zero rest mass, much like photons.

5. **All of the above (e)**: This option suggests that all listed particles have no mass, which is not true since electrons and neutrinos have mass.

6. **None of the above (f)**: This option implies that none of the listed particles have no mass, which is not the case either, as both photons and gluons do.

### Conclusion:
The correct answer is **b. Photons** and **d. Gluons**. Both of these particles are massless. Therefore, while **"All of the above"** sounds appealing, it is incorrect because electrons and neutrinos do not fit the criteria.

### Final Answer
The particles that have no mass are **Photons (b)** and **Gluons (d)**.

Knowee AI · Accepted Answer