The observed slowing of a clock in the vicinity of a black hole is a prediction of?

[Addictedtomilk]

the Cosmological Principle.
the Roche Limit.
Special relativity.
General relativity.
Stellar nucleosynthesis.

 

[man]

relitivity

 

[ksjazzguitar]

General relativity.

 

[timetravel]

General relativity

 

[Unregistered]

What observational evidence do we have that stellar-death black holes really exist?