Final answer:
The index of the last element of an array with 50 elements is 49 in zero-based indexing languages such as Java, C, and Python, and it is 50 in one-based indexing languages like MATLAB.
Step-by-step explanation:
The index of the last element of an array with 50 elements depends on the programming language being used. In programming languages that use zero-based indexing, like Java, C, C++, and Python, arrays start with an index of 0. Therefore, the last index will be one less than the size of the array. For an array with 50 elements, the index of the last element would be 49.
In some other programming environments, like MATLAB or Fortran, which use one-based indexing, the indices start at 1. In these cases, the index of the last element of a 50-element array would be 50. It's important to be aware of the indexing convention used by the programming language you're working with.