Final answer:
When attending a military funeral in uniform, the salute should be rendered when the casket is being carried.
Step-by-step explanation:
When attending a military funeral in uniform, the salute should be rendered when the casket is being carried. This is a sign of respect and is typically done by all military personnel in attendance. Saluting upon arrival at the cemetery, during the playing of Taps, and during the firing of the rifle salute are also appropriate, but saluting when the casket is being carried is the most important moment to render a salute.