The Security Council is the most powerful body in the UN. It is responsible for maintainin

g international peace, and for restoring peace when conflicts arise. Its decisions are binding on all UN members. The Security Council has the power to define what is a threat to security, to determine how the UN should respond, and to enforce its decisions by ordering UN members to take certain actions. The Council convenes（召集）any time there is a threat to peace. A representative from each member country who sits on the Council must be available at all times so that the Council can meet at a moment’s notice. The Security Council also frequently meets at the request of a UN member - often a nation with a grievance about another nation’s actions.

The Security Council has 15 members; five of which hold permanent seats. The Assembly elects the other ten members for two-year terms. The five permanent members - the United States, Britain, France, Russia (formerly the Soviet Union), and China - have the most power. These nations were the winning powers at the end of World War II, and they still represent the bulk of the world’s military might. Decisions of the Council require nine votes. But any one of the permanent members can veto an important decision. This authority is known as the veto right of the great powers. As a result, the Council is effective only when its permanent members can reach a consensus（一致同意）.

The Council has a variety of ways it can try to resolve conflicts among countries. Usually the Council’s first step is to encourage the countries to settle their disagreements without violence. The Council can mediate a dispute or recommend guidelines for a settlement. It can send peacekeeping troops into a distressed area. If war breaks out, the Council can call for a ceasefire. It can enforce its decisions by imposing economic sanctions on a country, or through joint military action.

Which is TRUE in the following statements according to the passage？

A.The Security Council convenes annually.

B.All UN members should abide by the decisions adopted by the Security Council.

C.Although one member seriously complains about another member’s action, the Security Council will not convene at its request.

D.The five permanent members of the Security Council hold less than one half armed forces in the world.

The Security Council is effective only when its permanent members can reach a consensus because ____.A.every permanent member has the veto right of great powers

B.all the permanent members won in the World War II

C.the other members of the Security Council are in the charge of the permanent members

D.of some other reasons not mentioned in this passage

One motion（提议）is adopted by the Security Council only if ____.A.14 of 15 members accept this motion

B.all the members have no objection to the motion

C.9 members agree on it and all the permanent members approve of it

D.all the permanent members pass it

The passage introduces all things about the Security Council EXCEPT____.A.mission

B.membership

C.rights

D.history

The last paragraph of this passage may be concluded with the statement that ____.A.UN gives priority to peaceful settlement of the conflicts among countries

B.the peacekeeping troops are most powerful in the conflicts between countries

C.economic sanction will be imposed on the countries involved in war

D.joint military action is the last resort of the Security Council in dealing with conflicts between among countries

请帮忙给出每个问题的正确答案和分析，谢谢！