Mantle of the earth crust is ?
Step 1: The Earth's structure is divided into crust, mantle, and core.
Step 2: The mantle lies below the crust and extends up to 2,900 km deep.
Step 3: It consists of semi-fluid silicate minerals, enabling tectonic plate movement (asthenosphere). \[ \boxed{\text{Semi-fluid mineral matter}} \]
| A. | Kalahari | 1. | South America |
| B. | Atacama | 2. | Australia |
| C. | Thar | 3. | Africa |
| D. | Great Victoria | 4. | Asia |