The objective test is not very satisfactory becaus

单项选择题

In ancient (古代) time the most important examinations were spoken, not written. In the schools of ancient Greece and Rome, testing usually consisted of saying poetry aloud or giving speeches.
In the European universities of the Middle Ages, students who were working for advanced degrees had to discuss questions in their field of study of the subject. This custom exists today as part of the work of testing candidates (候选人) for a master’s or doctor’s degree.
Generally, however, modern examinations are written. Two types of tests are commonly used in modern schools. The first type is sometimes called an objective (客观性) test, it is intended to deal with facts, not personal opinions. To make up an objective test, the teacher writes a series of questions, each of which has only one correct answer. Along with each question the teacher writes the correct answer and also three statements that look like answers to students who have not learned the material properly.
The student has just one task: he must recognize the correct answer and copy its letter or number on his examination paper.
For testing a student’s memory of facts and details, the objective test has advantages. It can find out a great deal about the student’s range of knowledge.
For testing some kinds of learning, however, such a test is not very satisfactory. A lucky student may guess the correct answer without really knowing the material.

The objective test is not very satisfactory because ______.

A．it is easy and quick to score
B．the teacher can find out a great deal about the student’s range of knowledge in a short time
C．it shows how deeply the student has thought about the subject
D．it contains element of luck