The correct answer is C. Examination of physical existence and valuation of assets.
Verification is the process of ensuring that the information in the financial statements is accurate and complete. It is done by examining the underlying documents and records, and by performing physical inspections of assets.
Option A is incorrect because examination of journal and ledger is only one part of the verification process.
Option B is incorrect because examination of voucher relating to assets is also only one part of the verification process.
Option D is incorrect because calculation of the value of assets is not the same as verification. Verification is the process of ensuring that the information in the financial statements is accurate and complete, while calculation of the value of assets is the process of determining the fair market value of an asset.