Which One of the Following Paper-Pencil Assessments Is Most Likely

Which one of the following paper-pencil assessments is most likely to have a reliability problem when the teacher scores students' responses?

A) Ms.Gibbons asks students to describe the "first Thanksgiving" in one or two pages.
B) Mr.Hammond gives 50 true-false questions about the geography of Russia.
C) Ms.Saunders administers a 30-item multiple-choice test about invertebrates.
D) Mr.Siebert gives a 10-word spelling test.