Part A:
The best inference that can be made about Mrs. Whatsit at this point in the story is "She can tell what people are thinking." This suggests that she has a deeper understanding or insight that goes beyond the surface level, indicating her otherworldly nature.
Part B:
The quotation from the text that best supports the answer to Part A is “'The tesseract—” Mrs. Murry whispered. 'What did she mean? How could she have known?'” This suggests that Mrs. Whatsit possesses knowledge that surprises and confuses those around her, supporting the idea that she has the ability to perceive thoughts or knowledge that is not readily apparent to others.