The authorities inflicted harsh penalty on him for indulging in forgery.

commendation
default
concession
reward

The correct answer is A. commendation.

The other options are:

  • B. default: a failure to meet a financial obligation or to fulfill a legal requirement.
  • C. concession: a thing that is granted or conceded, especially as a compromise.
  • D. reward: a thing given in recognition of service, effort, or achievement.

In this case, the authorities inflicted harsh penalty on him for indulging in forgery. This means that they punished him severely for committing a crime. The other options do not make sense in this context.