One inch is equal to ____ CM

Step 1: Identify the standard conversion factor for inches to centimeters.
The exact definition is:
$1\,inch = 2.54\,\text{cm}$

Step 2: Verify using millimeter definition (optional confirmation).
1 inch $= 25.4$ mm exactly.
Since $1$ cm $= 10$ mm,
$1\,inch = 25.4\,mm \times \frac{1\,cm}{10\,mm} = 2.54\,\text{cm}$

Step 3: Compare with given options (all in cm).
(a) $2.34$ cm $\neq 2.54$ cm
(b) $2.44$ cm $\neq 2.54$ cm
(c) $2.54$ cm $=$ $2.54$ cm (matches)
(d) None of these (incorrect, since (c) matches)

(c)