Which of the following is/are context free? (multi-select question)

A. {0^n1^n}

B. A language {a^i b^j c^k} such that either i is not equal to j or j is not equal to k. The alphabet is {a, b, c}. That is, the set of strings of as followed by bs followed by cs, such that there are a different number of as and bs or a different number of bs and cs.

C. the set of strings over 0 and 1 with odd length.

D. All positive integer numbers