A. Asif Ali Zardari
B. Qazi Faez Isa
C. Sikandar Sultan Raja
D. Yousuf Raza Gilani
Submitted by: Areesha Khan
Explanation: Senate Chairman Yousuf Raza Gilani, serving as the acting president at the time, signed the Elections Act (Amendment) Ordinance 2024.
The correct answer to the question: "Who was serving as the acting president when the Elections Act (Amendment) Ordinance 2024 was signed?" is "Yousuf Raza Gilani".