Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources (e.g., networks, servers, storage, applications, and services) that can be rapidly provisioned and released with minimal management effort or service provider interaction.

Explanation
With multiple tenants within the same hosting environment, any failure to properly classify data may lead to potential exposure to other customers and applications within the same environment.

Application virtualization is a software implementation that allows applications and programs to run in an isolated environment rather than directly interacting with the operating system. Sandboxing refers to segregating information or processes for security or testing purposes, but it's not directly related to isolation from the underlying operating system. Abstracting sounds similar to the correct term but is not pertinent to the question, and hosting is provided as an erroneous answer.