A. All I, II and III
Feedback As in the statement it is mentioned 'rejection due to inferior quality material and poor craftsmanship', it is well known that purchase dept is responsible for purchasing the inferior quality material. Again production dept is responsible for improper inspection. Hence investigation is compulsory for all the departments. Hence I follows. II follows because claim of company 'X' may be wrong. III follows because relationships with a previous client should always be kept up.