Identify the asset which can be easily converted into cash.

Option 1 -> Building is a fixed asset that requires lengthy legal procedures and finding suitable buyers, making it difficult to convert to cash quickly.

Option 2 -> Machinery is a fixed asset with limited buyers and requires time for valuation and sale, making it less liquid.

Option 3 -> Furniture is a fixed asset that may take time to sell and often loses significant value, making conversion to cash slower.

Option 4 -> Marketable securities are financial instruments like stocks and bonds traded in active markets that can be sold almost immediately at market price.

Hence, Option 4: Marketable securities -> These are highly liquid assets that can be quickly sold in financial markets and converted into cash with minimal delay or loss in value, making them the most easily convertible asset among all options -> correct