Which Prediction of the Theory of General Relativity Was the First

Which prediction of the theory of general relativity was the first to be tested by scientists?

A) The Earth will experience a solar eclipse in 1919.
B) Mercury will advance in its orbit by 43 seconds of arc.
C) The strong gravitational field of the Sun will bend light coming from a distant star.
D) Newtonian physics applies only to large masses.
E) Length contraction will occur in particle accelerators.