The formulae for illumination of surface = . . . . . . . .

A. $$\frac{{{\text{candle of source}}}}{{{\text{distance in meters}}}} \times \sec \theta $$

B. $$\frac{{{\text{candle of source}}}}{{{{\left( {{\text{distance}}} \right)}^3}}} \times \cos \theta $$

C. $$\frac{{{\text{candle of source}}}}{{{{\left( {{\text{distance in meters}}} \right)}^2}}} \times \cos \theta $$

D. $$\frac{{{{\left( {{\text{distance in meters}}} \right)}^2}}}{{{\text{candle of source}}}} \times \cos \theta $$

Answer: Option C