Initializing BitVector32 to True

Question:
You are developing an application to assist the user in conducting electronic surveys.
The survey consists of 25 true-or-false questions. You need to perform the following tasks:
- Initialize each answer to true.
- Minimize the amount of memory used by each survey.
Which storage option should you choose?
A. BitVector32 answers = new BitVector32(1);
B. BitVector32 answers = new BitVector32(-1);
C. BitArray answers = new BitArray(1);
D. BitArray answers = new BitArray(-1);Answer: B I think BitVector32 needs less memory than BitArray.. what about -1? -1 stands for True?
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