C. Plant and Machinery

Explanation:
A floating charge is a security interest over a company’s assets that are subject to change, such as inventory (stock-in-trade) and accounts receivable. It allows the company to use and dispose of these assets in the ordinary course of business. However, fixed assets like plant and machinery are typically not covered by a floating charge; instead, they are subject to fixed charges. Therefore, among the options provided, plant and machinery would not be included under a floating charge.