What is the definition of " honour" ?

  "Honour" means that the issuing bank undertakes:

  a. to ______ at sight if the credit is available by sight payment.

  b. to ______ a deferred payment undertaking and ______ at maturity if the credit is available by deferred payment.

  c. to ______ a bill of exchange ("draft" ) drawn by the beneficiary and ______ at maturity if the credit is available by acceptance.