Working of rocket or jet is based on:-

Options

A. Newton's law
B. Newton's II law
C. Newton's III law
D. All the three laws

Explanation

### Step-by-Step Solution:

1. **Understanding Rocket Propulsion**:
- Rockets and jets operate on the principle of action and reaction as described by Newton's Third Law of Motion. According to this law, for every action, there is an equal and opposite reaction.

2. **Expulsion of Exhaust**:
- When a rocket expels exhaust gases at high speed in one direction (downward), it creates a reaction force that propels the rocket in the opposite direction (upward). This expulsion of gases occurs at a tremendous speed.

3. **Force and Thrust**:
- The force exerted by the expelled gases creates thrust. The greater the speed and mass of the exhaust gases expelled, the greater the thrust generated. This thrust is what allows the rocket to overcome gravitational pull and ascend into space.

4. **Working in Vacuum**:
- One of the unique aspects of rocket propulsion is that it can work in a vacuum (space) where there is no air. The rocket does not rely on the surrounding air for propulsion; it only needs to expel gases to create thrust.

5. **Conclusion**:
- Therefore, the working of a rocket or jet is based on Newton's Third Law of Motion, which states that the action of expelling exhaust gases results in a reaction that propels the rocket upward.

### Final Answer:
The working of a rocket or jet is based on Newton's Third Law of Motion.

---