Final answer:
The correct answer is D) last, as the last part of a meter's name indicates the number of feet in a line of verse, with terms like monometer, dimeter, and trimeter specifying one, two, and three feet, respectively.
Step-by-step explanation:
The part of a meter's name that refers to the number of feet in a line is the last part. The lengths of lines of verse are described according to the number of feet they contain. For example, a line with one foot is called a monometer, a line of two feet is a dimeter, a line of three feet is a trimeter, and this pattern continues with tetrameter for four feet, pentameter for five feet, hexameter for six feet, heptameter for seven feet, and octameter for eight feet. Thus, the correct answer is D) last.