Explanation
The correct spelling is A: Complainant.
Complainant is a noun that refers to a person who makes a complaint or brings a legal action against someone. It is commonly used in legal and formal contexts.
Option B, "Complanant," is an incorrect spelling of the word.
Option C, "Complenant," is also an incorrect spelling.
Option D, "Complainent," is an incorrect spelling as well.
Therefore, option A, "Complainant," is the only correct spelling of the word.
