________ is a measure of the gravitational force acting on an object.

Options

A. mass
B. weight
C. pressure
D. none of these.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a term that measures the gravitational force acting on an object. We need to identify which of the given options correctly represents this concept.

2. **Reviewing the Options**:
- **Option 1: Mass** - Mass is a property of matter that quantifies the amount of substance in an object. It does not measure the gravitational force.
- **Option 2: Weight** - Weight is defined as the force exerted by gravity on an object. It can be calculated using the formula:
\[ \text{Weight (W)} = \text{mass (m)} \times \text{acceleration due to gravity (g)} \]
where \( g \) is approximately \( 9.8 \, \text{m/s}^2 \) on the surface of the Earth.
- **Option 3: Pressure** - Pressure is defined as the force applied per unit area. It does not relate to gravitational force directly.
- **Option 4: None of these** - This option suggests that none of the previous options are correct, which we need to evaluate.

3. **Analyzing the Correct Answer**: Since weight is directly related to the gravitational force acting on an object (as it is the force that results from gravity), we can conclude that:
\[ \text{Weight is the measure of the gravitational force acting on an object.} \]

4. **Final Answer**: Therefore, the correct answer to the question is **Weight**.

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