The Justinian Code is important because it is a

A. legal system many European countries have used that organizes and explains the laws
B. Military system that is still currently used throughout the world
C. Guide for the education of children that has influenced Eastern European schools
D. Set of rules for the people who practice medicine that doctors use today

A. legal system many European countries have used that organizes and explains the laws

The Justinian Code is important because it is a legal system many European countries have used that organizes and explains the laws. To reach this answer, you can analyze each option and see which one aligns with the description of the Justinian Code.

Option A states that the Justinian Code is a legal system, which matches the description of the Justinian Code as a set of laws. It also mentions that this system has been used by many European countries, which is accurate as the Justinian Code influenced the legal systems of many European nations. Therefore, option A is the correct answer.

Option B states that the Justinian Code is a military system that is still currently used throughout the world. However, this is not accurate as the Justinian Code primarily deals with legal matters and not military affairs.

Option C claims that the Justinian Code is a guide for the education of children that has influenced Eastern European schools. Although education and Eastern European schools exist, the Justinian Code does not pertain to education or school curricula.

Option D suggests that the Justinian Code is a set of rules for the people who practice medicine that doctors use today. This claim is incorrect, as the Justinian Code deals primarily with legal matters and has no direct connection to medicine or healthcare.

Therefore, the correct answer is option A, which states that the Justinian Code is a legal system many European countries have used that organizes and explains the laws.

The correct answer is A. The Justinian Code is important because it is a legal system many European countries have used that organizes and explains the laws.