Least count of a vernier callipers is `0.01 cm`. Using this, the diameter of a sphere is measured as `1.95 cm`. Radius of the sphere to the correct significant figure will be

Options

A. `0.98 cm`
B. `0.975 cm`
C. `1.0 cm`
D. `1 cm`

Explanation

To find the radius of the sphere to the correct significant figures, follow these steps:

### Step 1: Understand the given data
- The least count of the vernier calipers is `0.01 cm`.
- The measured diameter of the sphere is `1.95 cm`.

### Step 2: Calculate the radius
The radius \( r \) of the sphere is half of the diameter \( d \):
\[ r = \frac{d}{2} \]
Substituting the value of the diameter:
\[ r = \frac{1.95 \, \text{cm}}{2} = 0.975 \, \text{cm} \]

### Step 3: Determine the significant figures
The least count of the vernier calipers is `0.01 cm`, which indicates that the measurement can be accurate to two decimal places. The diameter is measured as `1.95 cm`, which has three significant figures. However, since the least count is `0.01 cm`, the radius should be reported with the same precision.

### Step 4: Round the radius to the correct significant figures
Since the least count limits the precision, we round `0.975 cm` to two decimal places:
\[ 0.975 \, \text{cm} \approx 0.98 \, \text{cm} \]

### Final Answer
The radius of the sphere, to the correct significant figures, is:
\[ \boxed{0.98 \, \text{cm}} \]

---