Gestation period refers to the period between what

Gestation period: Fetal development period from the time of conception until birth. For humans, the full gestation period is normally 9 months. The word "gestation" comes from the Latin "gestare" meaning "to carry or to bear."

d. There is no slope.

Step-by-step explanation:

We know that slope =

For the given table, since there is no change in x coordinate .

Thus the change in x coordinate is 0.

Therefore, slope=

which means the slope does not exist.

Hence, (d) is the right option. There is no slope.