Explanation:

All of the above statements are correct.
About Properties of Lithium

• It is a chemical element with the symbol Li.
• It is a soft, silvery-white metal.
• Under standard conditions, it is the lightest metal and the lightest solid element.
• It is highly reactive and flammable, and must be stored in mineral oil.
• Lithium has become the new 'white gold' as the demand for high performing rechargeable batteries is rising.

Hence option 4th is correct.