The correct option is (c).
Explanation
Temperature is a physical quantity expressing hotness or coldness, measured using various scales. The relationship between the Celsius scale and the Kelvin scale is fundamental to thermodynamics and the study of matter.
Statement 1 is Correct:
The Kelvin (K) is the base unit of thermodynamic temperature in the International System of Units (SI). Unlike the Celsius or Fahrenheit scales, the Kelvin scale is an absolute scale where 0 K represents absolute zero.
Statement 2 is Incorrect:
The relationship between the Kelvin scale ($T$) and the Celsius scale ($t$) is given by the formula:
$T (K) = t (^\circ C) + 273.15$
Therefore, to convert a temperature from Celsius to Kelvin, one must add 273.15 (often rounded to 273) to the given Celsius temperature, not subtract.
Statement 3 is Correct:
On the Celsius scale, the freezing point of water is defined as $0^\circ C$. Based on the conversion formula ($0 + 273.15$), $0^\circ C$ is equivalent to 273.15 K.
Key Takeaway:
The Kelvin is the SI unit of temperature. The conversion formula is $K = ^\circ C + 273.15$.