A.I. Explanation:

Option 1: "They have worse ability than nine-month-olds in distinguishing some faces."

Explanation: This option is incorrect because the text states that six-month-olds are better than nine-month-olds at recognizing certain faces, specifically mentioning their ability to distinguish between human and non-human faces. Therefore, the claim that they have worse ability contradicts the information provided.

Option 2: "They are better than nine-month-olds in everything."

Explanation: This option is incorrect as it overgeneralizes the statement made in the text. The woman mentions that six-month-olds are better than nine-month-olds specifically in recognizing certain faces, not in everything. Thus, this option presents partial information that is misleading.

Option 3: "They can’t distinguish non-human faces."

Explanation: This option is incorrect because the text explicitly states that six-month-olds are equally good at distinguishing between non-human faces as they are at distinguishing between human faces. Therefore, the claim that they cannot distinguish non-human faces is false.

Option 4: "They can both distinguish non-human faces and human faces."

Explanation: This option is correct as it accurately reflects the information in the text. The woman explains that six-month-olds are capable of distinguishing both non-human and human faces, highlighting their ability in this area. This aligns perfectly with the main idea presented in the text.