Correct Option: C

Low emissivity coating on a curtain system leads to:
Visible Light Transmission (VLT): The percentage of visible light that is transmitted through the glazing assembly. This is the essential characteristic for daylighting calculations. A perfectly clear window would have a VLT of 100 per cent. Most practical assemblies for architectural use are between 35 and 80 percent.
Solar Heat Gain Coefficient (SH GC): The percentage of total solar radiant energy that is transmitted through the assembly. This is the essential characteristic for solar gain calculations. For ordinary windows without special coatings, the SHGC and the VLT are the same and sometimes called the shading coefficient (SC).
However, with modern coated windows, the SHGC is almost always lower than the VLT. Such window systems are generically referred to as lowemissivity or low E and are used in most commercial construction.