She is slender in figure.

Answer: Option C

Slender : (of a person or part of the body) gracefully thin.
Strong : having the power to move heavy weights or perform other physically demanding tasks.
Well-built : (of a person) having a strong, sturdy physique.
Stout : (of a person) rather fat or of heavy build.
Slim : (of a person or their build) gracefully thin; slender.

Antonym of Slender is Stout