Final answer:
HDMI is used for connecting a workstation to a display over 30 feet away, which supports longer distances than DVI or DisplayPort, and SPDIF is not applicable since it is audio-only.
Therefore, the correct answer is: option d) hdmi.
Step-by-step explanation:
To connect your workstation to a large, high-definition screen that is over 30 feet away for displaying a video presentation, the best port option to support the transmission distance without signal degradation is HDMI.
Although HDMI signals typically start to degrade after about 50 feet without the help of a signal booster or active cable, it still offers a significant advantage over the distance limitations of DVI, which degrades after about 15 feet, and DisplayPort, which has a maximum cable length of about 15 feet without a signal booster.
SPDIF (commonly written as S/PDIF) is not suitable for video as it is an audio interface only. Therefore, HDMI would be the most suitable choice for such a setup, especially considering the availability of active HDMI cables that preserve signal integrity over longer distances.