Given a text T, and several options, according to the question posed in the text T to choose the most appropriate option from the options as the answer, please directly output the most appropriate option, do not need to output the explanation.

To claim compliance with the GIPS standards, a firm is required to:
Option A:adhere to certain calculation methodologies.
Option B:conduct an independent third-party verification of its claim of compliance.
Option C:perform periodic internal compliance checks of its investment performance process.

Answer: A