Final answer:
The segment connecting the midpoints of two sides of a triangle and parallel to the third side, with half its length, is called the midsegment.
Step-by-step explanation:
Properties of the Midsegment in a Triangle
The segment described in the question is known as the midsegment of a triangle. A midsegment has two distinctive characteristics: it is always parallel to the third side of the triangle, and its length is half the length of that third side. Considering the options given, the correct answer is a) Midsegment of a Triangle.
For instance, in a triangle ABC, if D and E are the midpoints of sides AB and AC, respectively, then segment DE is the midsegment. By the geometric properties of midsegments, DE is parallel to side BC, and DE is equal to one-half of the length of BC, fulfilling the described properties.