Identify the part of the sentence that has an error from the options…

The correct answer is Option (4) → (D) Only

The idiom "at home in":

• To be at home in a subject means to be comfortable and confident with it, to know it well.
• The idiom is fixed and takes no article: "at home in", never "at the home in".
  Example: Ravi is quite at home in computer programming.

(A) Even after — Correct.

• It introduces the contrast: in spite of the tuitions, she is still weak in Maths.

(B) taking tuitions — Correct.

• It is the usual Indian English phrase for private coaching.

(C) my daughter — Correct.

(D) is not at the home — Incorrect.

• The article must go: "is not at home".
• Correct form: Even after taking tuitions, my daughter is not at home in Maths.

(E) in Maths — Correct.

• "In" is the preposition the idiom needs.