Final answer:
A consultant with a Visual Studio Enterprise subscription can use the software at Litware, Inc. as it is a per-user license, but the specific terms of the subscription should be reviewed for any restrictions.
Step-by-step explanation:
The consultant working at Litware, Inc with an active Visual Studio Enterprise subscription from his own organization is licensed to use the software at Litware, Inc, given that Visual Studio subscriptions are generally per-user licenses. This means that the subscription is attached to the user rather than the organization, allowing the use of the software both in the workplace of the consultant's primary organization and in the development environment at Litware, Inc. However, it is important to check the specific terms and conditions of the Visual Studio Enterprise subscription, as there may be certain restrictions or requirements that apply when using the subscription in client environments such as Litware, Inc.