During a routine internal audit at a manufacturing company, the auditor discovers that the inventory records do not match the physical stock. What should the auditor$$s next step be to address this discrepancy?

A$).$ Immediately accuse the inventory manager of fraud.

B$).$ Adjust the records to match the physical stock without investigation.

C$).$ Ignore the discrepancy as it$$s probably a minor error.

D$).$ Investigate the discrepancy further to understand its cause and recommend corrective measures.