Final answer:
The correct option is Retrograde motion.
The object moving eastward on the ecliptic exhibits direct motion, which is the typical eastward movement of planets as they orbit the Sun. Retrograde motion occurs as an apparent motion when Earth passes another planet, causing it to seem like it moves westward. This retrograde motion is simply a matter of perspective from Earth.
Step-by-step explanation:
The motion of an object moving eastward on the ecliptic is generally referred to as direct motion. Planets usually move in this eastward direction as they orbit the Sun. However, an interesting phenomenon known as retrograde motion occurs when, from our vantage point on Earth, a planet appears to move westward against the background stars. This backward movement is observed when Earth, which orbits faster, passes another planet. As Earth continues in its orbit, the apparent motion switches back to the normal eastward or direct motion.
It's important to note that this retrograde motion is only an apparent motion caused by our perspective from Earth. The planets continue their eastward orbit around the Sun even during this period. This perception was a significant issue in early astronomy and led to complex models like Ptolemy's epicycles to explain. Thanks to modern astronomy, we better understand our solar system's principles and can attribute these observations to relative motion between planets.