What is the purpose of the second article? ( )

(单选题)If you’ve played with magnets, you know that opposite poles (单选题)To keep up with the infrastructure ( ) the profession als (单选题)Most of these resources are ( ) towards paper-writing and (单选题)Land is a major social and political issue, very explosive a (单选题)Advertising is ( ) into every aspect of our social life, (单选题)She was able to get the government and ( ) companies to h (单选题)Provision of medical care is classified into primary, second (单选题)Differential diagnosis methods help to rule ( ) unrelated (单选题)Hawass said the collection of workers’ tombs, some of ( ) (单选题)( ) the brain’s workings is a tremendous challenge and, j