Answer:
Options (C) and (F).
Step-by-step explanation:
Constant speed of an object is represented by the flat segment (a line parallel to the x-axis) on the graph of velocity and time.
In other words, flat segments represents no change in the velocity with respect to the time.
From the graph attached,
Being flat segments, C and F will represent the constant speed.
Therefore, Options (C) and (F) will be the correct options.