The correct answer is: Hazrat Arqam (RA).

In the early days of Islam, when Muslims were small in number and faced severe persecution from the Quraysh of Makkah, they needed a safe place to gather, pray, and learn about Islam. During this critical time, a noble companion named **Hazrat Arqam bin Abi Arqam (RA)** offered his house for this noble cause.

Hazrat Arqam’s house was located at the foot of Mount Safa in Makkah. It was known as **Dar-e-Arqam**, and it became the first secret center for the preaching and teaching of Islam. This house played a vital role in the early development of the Muslim community. It was here that Prophet Muhammad (SAW) would meet with his companions to teach them the Quran, guide them in matters of faith, and strengthen their unity and resolve.

Because of the secret location and the loyalty of those attending, Dar-e-Arqam remained unknown to the enemies of Islam for a long time. Many prominent Sahaba (companions), such as Hazrat Umar bin Khattab (RA), accepted Islam through the influence and teachings at this house. In fact, when Hazrat Umar (RA) accepted Islam, he went directly to Dar-e-Arqam to announce his faith.

The house of Hazrat Arqam (RA) became a symbol of dedication, support, and protection for the message of Islam. It shows how even a single home, when offered sincerely for the sake of Allah, can become a pillar in the foundation of a great movement.

Therefore, the correct answer is **Hazrat Arqam (RA)** — whose house served as the first base of Islamic preaching in secrecy and safety.