Q:

Select the option that makes the correct use of “unsustainable”, as used in the passage, to fill in the blank space.

• 1
  In the long run, the ______ officials followed emergency procedures
• 2
  Emergency procedures were _______ by the officials
• 3
  Officials reported an ________ set of events during the emergency
• 4
  Officials admit that the emergency system is _______ in the longer run.