Step 1: Reference to the chapter "Bholi".
In the story “Bholi” by K.A. Abbas, Ramlal is the father of four daughters and one son. Among the daughters, Radha is mentioned as the eldest. Step 2: Clarifying the names.
- Sulekha is Bholi’s real name (the youngest daughter).
- Kamala and Rekha are other daughters.
- Radha is clearly identified as the eldest. Final Answer:
\[
\boxed{\text{Radha}}
\]