Which of the following is not a branch of physics?

Options

A. Mechanics
B. Optics
C. Cytogenetics
D. Electrodynamics

Explanation

To determine which of the following options is not a branch of physics, we will analyze each option provided:

1. **Mechanics**: This is a well-known branch of physics that deals with the motion of objects and the forces acting upon them. It encompasses concepts such as velocity, acceleration, and the laws of motion.

2. **Optics**: This branch of physics focuses on the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it, such as lenses and mirrors.

3. **Cytogenetics**: This is a field of study that combines cytology (the study of cells) and genetics. It focuses on the structure and function of chromosomes and the inheritance of genetic traits. Cytogenetics is primarily a branch of biology, not physics.

4. **Electrodynamics**: This branch of physics deals with the study of electric charges in motion and the forces and fields associated with them. It encompasses concepts such as electric currents, magnetic fields, and electromagnetic waves.

Based on this analysis, we can conclude that the option that is not a branch of physics is **Cytogenetics**.

**Final Answer**: Cytogenetics is not a branch of physics.

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