Which of the following may be used to explain a mirage? i. layers of air near the road surface have varying refractive indices in hot weather. ii. road surfaces sometimes become good reflectors in hot weathers. iii. light from the sky can be reflected upwards after coming close to the road surface.

• A.ii only
• B.ii and iii only
• C.i and iii only
• D.i, ii, and iii only
• E.