In the equation for transmittance, It represents which of the following?

In the context of the equation for transmittance, It represents the final light intensity that emerges from a medium after passing through it. Transmittance is defined as the ratio of the intensity of light that passes through a sample (the transmitted intensity, It) to the intensity of the incident light (I0). In mathematical terms, transmittance (T) can be expressed as:

[ T = \frac{I_t}{I_0} ]

This means that It is the intensity of the light that has not been absorbed or scattered by the sample, thus it is essential to consider It as the final light intensity that is detected after interaction with the sample.

The other options refer to different concepts related to light intensity that do not align with the definition of transmittance in this context.