The ‘Paris Agreement’ adopted in Conference of the Parties (COP 21) in

The ‘Paris Agreement’ adopted in Conference of the Parties (COP 21) in December 2015 will be effective provided the document is signed by:

51 UNFCCC parties accounting for at least 51% of global greenhouse gas emission
51 UNFCCC parties accounting for at least 55% of global greenhouse gas emission
55 UNFCCC parties accounting for at least 55% of global greenhouse gas emission
75 UNFCCC parties accounting for at least 51% of global greenhouse gas emission
This question was previously asked in
UPSC CAPF – 2016
The correct answer is C.
The Paris Agreement adopted in December 2015 required ratification, acceptance, approval, or accession by at least 55 Parties to the UNFCCC which together account for at least 55% of the total global greenhouse gas emissions for it to enter into force. This specific condition was met in October 2016, leading to the Agreement’s entry into force on November 4, 2016.
This dual requirement (number of Parties and percentage of emissions) was designed to ensure that the agreement had broad support and covered a significant portion of global emissions before becoming legally binding.