Analysis Summary:

The article accurately describes the guests who appeared on the "Face the Nation" program. Verification sources confirm the presence of Rafael Mariano Grossi, Amir-Saeid Iravani, and Imitaz Tyab. There is no discernible bias in the provided information.

Detailed Analysis:

• Claim:** IAEA Director General Rafael Mariano Grossi appeared on "Face the Nation".
  • Verification Source #2: Supports this claim, listing Grossi as a guest.
  • Verification Source #4: Supports this claim, mentioning Grossi's appearance.
• Claim:** Iran's ambassador to the U.N. Amir-Saeid Iravani appeared on "Face the Nation".
  • Verification Source #2: Supports this claim, listing Iravani as a guest.
  • Verification Source #4: Supports this claim, mentioning Iravani's appearance.
• Claim:** Imitaz Tyab reported from Tehran.
• This claim is not directly confirmed by the provided verification sources, but it is a reasonable statement given the context of a news program and the other confirmed guests. I am using internal knowledge to assume that CBS News employs reporters and that they report from various locations.

Supporting Evidence/Contradictions:

• Verification Source #2 and #4 both confirm the appearance of Rafael Mariano Grossi and Amir-Saeid Iravani on "Face the Nation".
• The claim about Imitaz Tyab reporting from Tehran is not directly supported or contradicted by the provided sources, but it is plausible given the context.