Step 1: Understand Article 16.
Article 16 guarantees equality of opportunity in matters of public employment.
Step 2: Analyze the specific clauses.
Article 16(4): Allows the state to make provisions for the reservation of appointments in favor of any backward class of citizens.
In the case of \textit{Indra Sawhney v.
Union of India}, the Supreme Court held that reservation under 16(4) applies only to initial appointments, not to promotions.
Article 16(4A): To overcome this judgment, Parliament inserted clause (4A) via the 77th Amendment Act, 1995.
This clause specifically empowers the state to make provisions for reservation in matters of promotion for SCs and STs.
It was later amended by the 85th Amendment Act, 2001, to also include "consequential seniority.
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Therefore, the provision that facilitates reservation in promotions with consequential seniority is Article 16(4A).