Player of the tournament Sanju Samson is one of four India players in the XI, alongside Ishan Kishan, Hardik Pandya and Jasprit Bumrah.
Markram was included after scoring 286 runs – including three half-centuries - as Proteas reached the semi-finals before losing to New Zealand.
Ngidi impressed in the global tournament taking 12 wickets at an average of 15.58, including four against Canada and three apiece against Afghanistan and West Indies.
The seamer also had a miserly spell against India that yielded just 15 runs from four overs.
The West Indies' Jason Holder earns his place in the side thanks to strong performances with bat and ball.
Holder took three wickets against Scotland and four against Nepal before stepping up with the bat in the Super Eights.
The team is rounded out by Zimbabwe's Blessing Muzarabani, who was key to his side's stunning group stage performances.
The lanky seamer took 4-17 as Zimbabwe beat Australia and finished the group stage with nine wickets.
The team's 12th player is Shadley van Schalkwyk, who took 13 wickets for the USA at a rate of just 6.84 and economy of 6.80.
T20 World Cup Team of the Tournament
1. Sahibzada Farhan
2. Sanju Samson (wicketkeeper)
3. Ishan Kishan
4. Aiden Markram (captain)
5. Hardik Pandya
6. Will Jacks
7. Jason Holder
8. Jasprit Bumrah
9. Lungi Ngidi
10. Adil Rashid
11. Blessing Muzarabani
Proteas head coach Shukri Conrad is expecting Namibia to 'put their best foot forward' when the two countries clash for the first time in an ODI series that kicks off in Windhoek on Wednesday.
David Miller and Quinton de Kock have been included in the Proteas ODI squad for the three-match series at home against Australia that starts later this month.
Matthew Breetzke and Corbin Bosch have been added to the Proteas squad ahead of the three-match ODI series against Namibia that starts in Windhoek on Wednesday.
The Proteas produced a clinical all-round performance to beat Zimbabwe by 48 runs and claim the T20I tri-series title in Windhoek on Sunday.
