Spectrophotometer measures the transmittance or the absorbance, or both, of a particular wavelength or light after it has passed through a liquid sample. the liquid sample holder is commonly known as a cuvette. before the transmittance or absorbance of the sample is measured, a cuvette filled only with solvent, called the blank, is placed in the spectrophotometer. select the statement from the following that is true for why is a blank measured before the sample.
a. a blank is measured to remove the signal caused by the cuvette walls and solvent.
b. a blank is measured to calibrate the spectrophotometer's light source.
c. there is no reason to measure a blank before the sample.
d. a blank is measured to clean the spectrophotometer.