What Major Change Occurred to the Panama Canal in 2016

What major change occurred to the Panama Canal in 2016?

A) The canal was sold to the Chinese who then halted construction of the Nicaraguan Canal.
B) A new set of locks was added thereby allowing larger ships to pass through.
C) Control of the canal was given back to the United States as part of NAFTA.
D) The canal was closed as a result of the opening of the Nicaraguan Canal.
E) The Panamanian government restricted the passage of oil tankers because of environmental concerns.