Answer : Option A)
45.5%
Explanation : We use the formula of calculating energy efficiency which is as,
η (in %)= [

] X 100
where η is energy efficiency,
and P values are for energy out and in.
So plugging the given values, we get,
η (in %) = (11825.5 / 25978.8) X 100 =
45.5 %