If you need to be able to store numerical values

If you need to be able to store numerical values up to 2,100,000,000 in a variable and be able to store negative values into it at the same time (using the .NET Framework 2.0), what type of variables will you use to optimize the usage of memory?

Int32
UInt16
UInt32
Int16

Explanation

You need to use Int32, since this type can be used to store positive and negative numeric values in a range from -2,147,483,648 to +2,147,483,647.
UInt32 and UInt16 can not be used because they are used to store only positive values.
Int16 can not be used since its range of possible values is from -32768 to +32767.