What is the name of the distinctive greenstone that is found only in the South Island's riverbeds and has been carved by Māori for centuries into tools, weapons, and ornaments?

• A Pounamu (nephrite jade) ✓
• B Obsidian (mataa)
• C Argillite (pakohe)
• D Serpentine (tangiwai)

Pounamu holds immense cultural significance for Māori, particularly Ngāi Tahu, who are the legal kaitiaki (guardians) of all pounamu in the South Island under the Ngāi Tahu Settlement Act 1998.