The following are examples of a friendly fire, except one. Pick the exception.

In the context of fire-related incidents, the term "friendly fire" often refers to situations where fire is intentionally set or controlled in a way that it is generally safe and contained, typically leading to minimal damage or harm.

When considering the provided options, the correct identification of an exception lies in understanding the definitions of friendly fire scenarios:

Burning steaks on a BBQ, wood burning in a fireplace, and garbage being burnt in a fireplace are all instances where fire is intended and managed within designated areas meant for such activity. These scenarios denote situations where the fire is purposefully created for cooking or heating and is contained within a safe environment.

In contrast, the option related to "spark from a wood fireplace" does not fit the friendly fire category, primarily because a spark represents an uncontrolled element that could potentially escape and cause unwanted ignition or fires outside the intended area. While sparks may occur during the burning of firewood in a fireplace, they may not always be managed or anticipated, making them a less safe aspect of dealing with fire compared to the other options that involve controlled and deliberate uses of fire.

Thus, the proper understanding of what constitutes friendly fire enables the identification of the exception, which in this case, is the choice that relates to sparks.