The correct answer is: A. Spectrum of an oil flame
A continuous emission spectrum is a spectrum of light that contains all wavelengths of visible light. It is produced by a hot object, such as an oil flame, that emits light in all directions. The spectrum of an oil flame is continuous because the hot oil molecules are constantly moving and emitting light at all wavelengths.
The spectrum of a water molecule is not continuous. It is made up of a series of discrete lines, each of which corresponds to a different wavelength of light. This is because water molecules are arranged in a regular pattern, and they only emit light when the electrons in the molecule move from one energy level to another. The energy levels of the electrons in a water molecule are quantized, which means that they can only have certain values. This is why the spectrum of a water molecule is made up of a series of discrete lines.
The spectrum of an oil flame is an example of a continuous emission spectrum because it contains all wavelengths of visible light. The spectrum of a water molecule is not continuous because it is made up of a series of discrete lines.