Answer:
a one rotation of the planet on its axis
Step-by-step explanation:
The two types of motion that planets undergo are;
1) rotation of the planet about its axis
2) revolution of the planet around the sun.
In every planet there are days as shown in the image attached to the question. However, the length of day in each planet is determined by the time required for the planet to complete one rotation on its axis.
It takes the earth 1 earth day (24 hours) to complete rotation on its axis.