A fictitious asset is an asset that does not have a physical existence and cannot be seen or touched. Out of the options provided, the only asset that fits this description is "preliminary expenses." These are expenses that are incurred during the formation of a company, such as legal fees, registration fees, and expenses associated with issuing shares. These expenses are not tangible and cannot be physically touched or seen, and therefore, they are considered a fictitious asset. The other options, such as fixtures and fittings, land and buildings, and investments, are all physical assets that can be seen and touched. "Cash in hand" is also not a fictitious asset, as it is a real asset that represents the amount of cash held by a company at a given point in time.