2090
one of the big questions about mars is when or whether humans will ever be able to visit .
 transport: visit
Please tell me event type and its trigger word from given type options. Output format is "type: trigger".  Option: declare bankruptcy, transfer ownership, marry, die, phone write, arrest jail, convict, sue, transfer money, end organization, start organization, end position, merge organization, start position, transport, charge indict, elect, attack, injure, born, extradite, release parole, sentence, demonstrate, meet, trial hearing, divorce, nominate, fine, appeal, pardon, execute, acquit 
Text: {0} 
Answer:
 transport: visit