Aline spectrum is produced when an electron moves from one energy level a. to a higher energy level b. to a lower energy level c. into the nucleus d. to another position in the same sublevel

A line spectrum is termed after the fact that radiation (light) emitted is made up of a series of crisp lines. The wavelengths of lines are unique to an element and can create extremely complex patterns, and the further discussion can be defined as follows:

Whenever an electron goes to the lower energy level, it forms a line. Once an electron goes down to a lower energy orbit, it de-excites, generating a photon of a specified frequency.   Conversely, this photon might be emitted in any direction, not merely just like an incident photon.

Therefore, the final choice is "Option A" .

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A.

Only one reactant yields 2 or more products. meaning you will only have 1 product and it will break down into 2 or more products. eg. h2o -> h2 + o2