Which of the following has the dimensional formula \[M0L0T0\]?
Dimensionless quantities like refractive index, strain, and angles have no physical dimensions. As per NCERT Class 11 Chapter 2, dimensional analysis checks correctness and SI units define base and derived quantities. This principle confirms that Strain is correct because its dimensions and unit match the physical quantity asked.
Ref: NCERT Class 11 Physics > Chapter 2: Units and Measurements > Topic: SI Units and Dimensional Formulae