Mrs. Dorling's attire is mentioned in the short story, "The Browning Version" by Terence Rattigan. The author, R.C. Sherriff, describes Mrs. Dorling's attire when he visits her house to collect his belongings after his mother's death.

The correct answer is option 'A', which states that the author found Mrs. Dorling wearing his mother's green knitted cardigan. This choice is supported by the following details mentioned in the story:

1. Description of Mrs. Dorling: The author describes Mrs. Dorling as a middle-aged woman with a thin face and tired eyes. She is portrayed as a reserved and somewhat distant character.

2. The author's recognition of the cardigan: Upon entering Mrs. Dorling's house, the author notices a familiar smell of mothballs. He then sees Mrs. Dorling wearing a green knitted cardigan that he immediately recognizes as his mother's. This indicates that the author is able to identify the attire worn by Mrs. Dorling.

3. Emotional significance: The green knitted cardigan holds sentimental value for the author as it reminds him of his mother. He mentions that the cardigan was his mother's favorite and she used to wear it on chilly evenings. This emotional connection further emphasizes the recognition of the attire.

4. Mrs. Dorling's response: When the author comments on the cardigan, Mrs. Dorling seems surprised and unsure about its origin. She mentions that she found it in the cupboard and thought it was a nice color. This suggests that Mrs. Dorling was unaware that she was wearing the author's mother's cardigan.

Overall, the author finds Mrs. Dorling wearing his mother's green knitted cardigan. This detail helps to establish a connection between the author's past and his present, highlighting the theme of loss and remembrance in the story.