A

Step 1: When a white hot solid emits light, it produces a continuous spectrum.
Step 2: When this light passes through a sodium flame, the sodium atoms absorb certain wavelengths of light and emit them again, which results in the appearance of bright lines at specific wavelengths corresponding to sodium absorption.
Step 3: These bright yellow lines correspond to the sodium D-lines, which are typically at 5890 Å and 5896 Å.
Therefore, the spectrum of the emergent light shows bright yellow lines of sodium along with the continuous spectrum of the white hot solid.
Hence, the correct answer is A.