31. When a known concentration of analyte (with known molar absorptivity in pH 7.0 buffer) is added to a blank but unknown aqueous matrix (containing no analyte), the observed increase in absorbance is lower than predicted. Why might this happen (choose any/all that apply)? (a) Thermal decomposition of the analyte (b) The matrix pH may not be 7.0 (c) The analyte may associate with a matrix component (d) The matrix may emit light at the analyte absorption maximum (e) None of the above