Context: Read the passage and look at the picture.
The Sunda Trench is a deep-sea trench that formed as the Indo-Australian Plate collided with the Sunda Plate. Movement at this plate boundary can cause earthquakes and devastating tsunamis. A tsunami is a series of giant waves that may form when oceanic crust is suddenly lifted by an earthquake. In December 2004, an earthquake and the resulting tsunami affected millions of people in countries surrounding the Indian Ocean.
Complete the sentence.
The Sunda Trench formed at a () boundary.
A. convergent
B. transform
C. divergent
Choose the right answer from the options and respond with its letter.

A