Russian antivirus software supplier Kaspersky Lab announced on June 15 that an international virus writing group called 29a has created the world's first virus that can be transmitted between mobile phones. Spersky Lab said that on the 15th, the 29a team sent the code of the `` Carbill '' worm to some anti-virus manufacturers, which confirmed that the virus has the ability to spread between mobile phones. This paragraph of text is a piece of news in a newspaper. What is the most suitable subject for this paragraph of text? ['"Carbil" worm born in Russia.', "New contributions from B.29a's International Virus Compilation Group.", "World's first virus spread between mobile phones is born.", 'Anti-virus manufacturers confirm that viruses can be transmitted between mobile phones.']