In the following question, out of the four alternatives, select the alternative which is the best substitute of the phrase.
to easily bent; flexible.

* Pliable means easily bent, flexible, or easily influenced.
Putty is a paste-like material used as a sealant or filler.

Rigid means stiff and unyielding (the exact opposite).

Ductile means able to be drawn out into a thin wire (specifically used for metals).

Therefore, pliable is the best fit for the definition.