Definition: Compose a new way to ask the same question. The new question must be asking the exact same thing as the original question does. Without any other information, you should be able to tell that the original question and the new question are the same. Preserve bracketed phrases in your new question. You can change the rest of the question provided the above requirements are satisfied. The new question must have a natural, fluent formulation, as if it were composed by a native English speaker. You will be given three pieces of information to help you create better questions. Those are: "Answer": the answer to the question, e.g., "Honolulu". "Answer Type": the type of the answer, e.g., "Location". "Auxiliary Information" is a detailed description of some concepts mentioned in the question, if any.
Input: original question: Which survey is done in [Cerro Tololo Inter-American Observatory]
answer: 2mass
answer type: Astronomical Survey/Project Organization.
auxiliary information: The Cerro Tololo Inter-American Observatory is an astronomical observatory located on Cerro Tololo in the Coquimbo Region of northern Chile, with additional facilities located on Cerro Pach√≥n about 10 kilometres to the southeast. It is within the Coquimbo Region and approximately 80 kilometres east of La Serena, where support facilities are located. The site was identified by a team of scientists from Chile and the United States in 1959, and it was selected in 1962. Construction began in 1963 and regular astronomical observations commenced in 1965. Construction of large buildings on Cerro Tololo ended with the completion of the V√≠ctor M. Blanco Telescope in 1974, but smaller facilities have been built since then. Cerro Pach√≥n is still under development, with two large telescopes inaugurated since 2000, and one in the early stages of construction. The principal telescopes at CTIO are the 4 m V√≠ctor M. Blanco Telescope, named after Puerto Rican astronomer Victor Manuel Blanco, and the 4.1 m Southern Astrophysical Research telescope, which is situated on Cerro Pach√≥n.

[Cerro Tololo Inter-American Observatory] does which survey?