Answer:
C.) Mrs. Welland is Mrs. Mingott’s daughter.
Explanation:
Edith Wharton's "The age of Innocence" centers around Mr. Archer as he is about to marry May Welland.
Archer and May have come to an old Mrs. Mingott, the Mingott family matriarch, to set the date of the wedding.
Now, regarding the relations in the family, we know that Mrs. Welland is May's mother (since it is stated that Mr. Archer is her future son-in-law). Also, Mrs. Welland calls Mrs. Mingott "mamma" ("We must give them time to get to know each other a little better, mamma") suggesting that Mrs. Mingott is Mrs. Welland's mother and May's grandmother.
