Sentence Correction

Reporting that one of its many problems had been the recent extended sales slump in women's apparel, the seven-store retailer said it would start a three-month liquidation sale in all of its stores.

A its many problems had been the recent
B its many problems has been the recently
C its many problems is the recently
D their many problems is the recent
E their many problems has been the recent


Please help to give some trick for these problems...

D & E are out due to subject-verb mismatch.

B and C give the meaning that the sales slump were extended purposely.

guess the intended meaning is the persisting slump in sales that took place in the near past.

so recent extended sales slump of A is better than the recently extended sales slump of B and C