Synonym of MORIBUND

Answer: Option C

Stagnant : (of a body of water or the atmosphere of a confined space) having no current or flow and often having an unpleasant smell as a consequence.
Gloomy : dark or poorly lit, especially so as to appear depressing or frightening.
Dying : on the point of death.
Superfluous : unnecessary, especially through being more than enough.
Moribund : (of a person) at the point of death.

Synonym of Moribund is Dying