Sayyed Mohammad Al-Musawi,
Sayyed Mohammad al-Musawi is originally from Iraq and heads up the World Ahlul Bayt Islamic League in London. Other than being involved in various humanitarian projects, he frequently responds to religious questions. In the past, he has also spent significant time in India guiding the community.
The Marja' Al-A'la is the Marja' who is been followed by majority of the Shia scholars in the Hawzas (Islamic seminaries and religious knowledge centers). Now a days the majority of scholars refer to Ayatullah Al-Udhma Sayyed Ali Al-Sistani is the Marja' al-A'la.
Every Mujtahid acts upon his own verdicts because Taqleed is not on the Mujtahids but on the public.